Cucumber (Oi) kimchi is probably the most "easy" compared to normal.
3-4 Lebanese Cucumbers (or any pickling cucumber)
1.5 Tablespoons of Sea Salt
Handful of shredded carrots
Handful of Buchu (Korean Garlic Chives)
Kimchi Spice Sauce
1-3 Tablespoons of Gochugaru (Korean Chili Flakes, depending on how spicy you like it)
1 Nashi pear or Red Apple grated
1 Tablespoon of Honey or Raw Sugar
3-4 Garlic Cloves chopped finely or grated
1 tsp of grated ginger
1 tablespoon of Fish sauce
1 tsp of Soy Sauce
Cut cucumbers into bitesized pieces, about 4 cms long. Toss them in the sea salt, leave for 20 mins.
Brush off or lightly wash salt from cucumbers. Put into bowl with sauce and carrots/Buchu, mix well.
Put in a glass airtight container, leave on bench for 1-2 days to ferment, put in fridge, chill and serve.
White Kimchi is a bit more involved. You typically do whole napa leaves, put the filling in them and roll them up.
You can do it a quick way though and just toss everything in in a normal "quick" kimchi way.
https://mykoreankitchen.com/baek-kimchi-non-spicy-white-kimchi/ But I add about a handful of chopped chestnuts and about a tablespoon of pinenuts to that. Probably sub the red capsicum with a yellow one. You can also use apple instead of Nashi Pear.
If you don't want to do the wrapping/stuffing, then just toss it all in and pour the brine over. It's a light refreshing kimchi, salty and sweet, but has a really nice flavour. I also use it to make okonomiyaki if I don't have fresh cabbage. It really works perfectly like that.