I've done this many times. First don't use Biab for the recording part, use Real Band which is included. Biab only has one audio track available while RB is a full DAW with 48 tracks plus it will generate Biab parts. This allows you to do multiple takes of your vocals for example then you cut/paste the best parts of those tracks to make your final vocal track. Start reading the Real Band forum.

Otherwise, recording in an apartment is pretty obvious. Get used to everybody's schedules around you and then you schedule your recordings around them. I never had any problems with mixing, everybody has home theater sound systems so I would hear my neighbors watching a movie all the time. If I can hear them I don't care if they can hear me doing my mixes either as long as it's not too extreme. Forget headphones. I only use cans to check the mix not to do the mixing itself. You need a decent set of studio monitors.

Bob

Biab/RB latest build, Win 11 Pro, Ryzen 5 5600 G, 512 Gig SSD, 16 Gigs Ram, Steinberg UR22 MkII, Roland Sonic Cell, Kurzweil PC3, Hammond SK1, Korg PA3XPro, Garritan JABB, Hypercanvas, Sampletank 3, more.