For the best finish I would recommend spraying the pieces disassembled. You can rent a sprayer from most sherwin Williams stores for ~$50/day.

I’d recommend starting with a primer made for wood and top coat using a trim/cabinet paint like sherwin Williams emerald urethane or proclassic. Normal wall paint will be susceptible to chipping and discoloration in areas you touch often.

If you don’t want to spray, I’d still recommend painting disassembled and use the smallest nap roller you can find.

Can confirm that a hammer would probably be nessesary. I used to do building staking and even the 1/4” think lath we used for call outs took some swings of a 4lb sludge to get ~8” deep. A small diameter rod might work better but you’re still probably gonna be hammering to get any depth with it.