Facebook Groups posting [ Arbitrage ]

Hello Folks,

I'm new in Facebook groups promoting staffs, I have some questions if you don't mind :

1 - It's a good idea to start with "JARVEE" , I'm lost to do it manually ( no result )
2 - How to find the active and the right groups ?
3 - How to avoid the " pending approval by an admin" Groups ?
4 - it's ok to promote with an old FB accounts, that are not active in the past 3 years ?
5 - Why in some cases even when I share just a pic it's become ghosted no engagement even the group is so active ?

Thank you guys, I would appreciate any help,
Love you all

you can search by the keywords and see how many posts a day.
Most of the groups are designed to ask questions before allowing you to enter. Answer their questions, they usually let you in.
the old groups not meaning low engagement, it still has value to promote your products.
adjust your pic and content, maybe your pic not hit the point, whether the group is your target or not.

Thank you for your answer but I'm aware of all what you said