how do I add my mixamo custom character into Lyra

I tried watching several retargeting videos, can you recommend one that works, because I tried and some problems I encountered is I could not find the mannequin folder, or it is for unreal engine 4, or there is a tab that i do not see on my unreal engine, so I always end up unsuccessfully retargeting. Or there are plugins that I do not really know how to install because i double clicked it and it said it could not find unreal engine 5. I do not know where i saved unreal engine 5, is it in program files under epic?

What is bp in lyra bp? Base program?