I'd hope for this year, depends on the actions of the troops currently stationed in Belarus, the new Russian commander or if NATO or its constituents commit to action.
Belarussian inolvement would be neglible military, they would get absolutely destroyed and halted in their tracks if they attempted to attack the northern border. Rumours about Polish intervention in this case would escalate things enourmosly, probably resulting in a regime change in Belarus.
Like, the Russian surprise attack with fresh troops and materiel ( just a bit smaller than the force in Belarus ) failed to achieve any meaningful objectives. So, a somewhat armored Russian force ( less capable in training and materiel compared to the iniatial attack in Feb ) coupled with an ill-equpped, ill trained and de-motivated small Belarus force attacking a prepared, fortified and reinforced border would probably mean disaster for the attackers, not to mention the internal chaos it would create in Belarus. I see this force as a distraction and warning to Ukraine. Attacking would be absolute madness.
I think that the war will continue on these three things
1) The most important, western resolve and involvement. If the west stops their shipments ( with ammunition being most critical ) and humantarian/economic aid, Ukraine wont be able to sustain their state and their armed forces for long. Maybe a few months they can hold, but then it'll just collapse. And signs of western resolve waning are minimal, its probably the opposite with them now lobbying for increased support of major modern systems
2) Russian resolve. A majority of the russian people are backwater and totally loyal to the authoritarian regime, especially Putin. Russia doesnt have the capability to replace their losses at all, especially the modern parts. But they have the manpower and older systems to keep up defensivelly atleast. Also N U K E S. As their resolve probably wont fail, the war will continue. Both parties are in this shit deep at this point. Only possibility is an internal coup where Putin gets removed, i have no idea if this is realistic or not
3) For now, its mostly a stalemate. Russia has gained really bad rep by throwing hundreds ( if not thousands ) of missiles on civilian infrastructure, with some of these hitting civilian building causing civilian casualties, which ofc all western media will spin on. Ukraine is making small gains at Svatove/Kreminna, Wagner has achieved a breakthrough and captured Soledar ( increasing signs of a schism between Wagner and the Russian state could be interesting ), Ukraine is organizing and collecting mech/armored brigades for a counter-offensive. Ukraine isnt willing to secede the Donbass and Crimea for peace, Russia doesnt want to agree to Ukrainian terms of retreating back to the internationally recognized border and pay war reps. Zelensky is just a public figure, replacing him wouldnt nudge this at all in my opinion. As russia is much more consolidated around Putin, a coup/replacement of him could mean things. But this happening is very speculative and there are no clear signs that they could do this.
TL;DR
War will most likely continue for atleast the most part of 2023
