First of all, 'intersex' is not a true medial term. There is no agreed upon group of conditions that are considered intersex, which is why that infamous statistic that 1.7% of all humanity is intersex is thrown around by troons all the time. This would make intersex as common as the amount of natural red heads in the world. If that number seems high, that's because the gender studies professor who posited it, Anne Fausto-Sterling, included any and all chromosomal abnormalities and some hormonal conditions. She even counted things like regular XY men who's urethra wasn't in the right spot. There are people who argue PCOS counts as intersex. Nowadays the medical community is starting to view intersex purely as someone with a DSD, or disorder of sexual development. This would limit it to people who's genitalia does not match their chromosomes. This definition makes intersex only present in 0.018-0.05% of the population. Predictably, many intersex people (who weren't really intersex) chimped out when doctors refined the scope of the term.
First, let's look at sex chromosomal abnormalities, which are no longer thought to be true intersex by doctors. Hilariously, some of these conditions are only possible in men, and others in women.
Turner Syndrome
Women who only have one X chromosome. Symptoms include a wide, webbed neck, a broad chest with widely spaced nipples, short stature, heart defects, narrow and upwardly turned fingernails, low set ears, a low hairline at the back of the head, possible learning disabilities. They are always infertile (at least without medical help) and have normal female genitals.
Klinefelter Syndrome
Men who are XXY. Or XXXY. Or XXXXY. Symptoms include muscle weakness/chronic fatigue, small testicles, poor coordination, less body hair, tall height, low libido and gynecomastia. They are always infertile, and those with more X chromosomes have low IQ. Other than the small, poorly working testicles, they have typical male genitalia.
Jacobs Syndrome
Men who are XYY. Since the Y chromosome doesn't have a ton of genes on it, they got off pretty easily. The only symptoms are just being taller than average and a higher risk of mild learning disabilities. They have normal genitals and are fertile.
Then we get to the true DSD's. In a nutshell, this is basically people who appear phenotypically female (or have ambiguous genitals) but are XY/people who appear phenotypically male (or have ambiguous genitals) but are XX. It is important to note that hermaphrodism in humans (producing both ova and sperm) is utterly impossible. Human reproductive development is antagonistic- when one reproductive system is forming, it produces hormones that destroys any chance for the other one to form.
XX's with DSD are women who have ovaries and uterus but male-ish genitals. This is usually caused by a female fetus who was exposed to too much testosterone in the womb, causing the labia to fuse and resemble a scrotum, and the clitoris to enlarge and resemble a penis. While there are natural causes (an adrenal tumor in the mother during pregnancy, or a genetic condition that affects the fetuses adrenal gland) this disorder can also be artificially caused by pooners who didn't stop taking testosterone while pregnant with a girl. It is not fucking caused by a mother eating meat and smoking while pregnant. The ones with fucked up adrenal glands have significant effects on their health and often require medical intervention to not die. It also makes the women look masculinized, with dense body hair, facial hair, more muscle mass and a deeper voice. They sometimes still mensurate though.
In very, very rare cases, a fetus with XX chromosomes can have the SRY gene, which usually only sits on the Y chromosome, get translated onto one of the X's. The SRY gene is what causes masculinization in a fetus, and is more important than the Y chromosome itself. This is called de la Chapelle syndrome and often produces someone who looks typically male and has normal male genitals. They don't even have ovaries or uteruses, but because the testes are underdeveloped and undescended they are always infertile. Despite the chromosome oopsie with no actual Y being present, they are considered genetically men by the medical community.
XY's with DSD are similar. Sometimes it's men (XY) who have androgen insensitivity syndrome. While there are mild forms, when they have the 'complete' form their body can't react or respond to any testosterone so they develop an external vagina but have internal testes and no ovaries/uterus. The degrees of feminization vary but those with the complete AIS look outwardly female (though maybe a bit of a strong featured, mannish woman) and only find out about the condition when they fail to menstruate. Obviously, they are infertile and while they are "technically" men most just live life as a woman.
Then there's Swyer Syndrome, the opposite version of de la Chapelle. These are people with XY chromosomes who's SRY gene is absent or failed to activate. Since it's necessary for masculinization, the fetus develops into a phenotypical female with a vagina (or ambiguous genitals) and uterus. They don't have ovaries, so can't get pregnant naturally and won't go through puberty without HRT. They also do not menstruate. Most will live their life as a female.
FINALLY, we get to the weird shit. Things like mosaicism (45,X/46,XY karyotype AKA some cells lose the Y. They usually are men with normal penises, but some men have ambiguous or female genitals) and the super rare (only 500 known cases) and weird ovotesticular disorder. These are people with both ovarian and testicular tissue, and may even have one ovary and one testes! But wait... can't humans not be hermaphrodites? Well, no. Because the reproductive systems cancel each other out, this means they have one main functioning reproductive system and a vestigial, underdeveloped (or even just clumps of tissue) opposite one that does not work.
Sorry the spergout, but knowledge is power against troons who want to be double sex or third sex or whatever. Curiously, if you ask them what their intersex condition is they either make something up like the loser above or won't tell you.