Can I Use Steam Family sharing to play an origin (or ubisoft) Game?
Now I know many people probably asked this already but, my question is a little different from others: Can I Use Steam Family sharing to play an origin (or ubisoft) game if I don't own it on steam but I Do own it on origin (or Do own it on Ubi-connect)?
I am mainly asking this to see if I can get the related games achievements on steam while I own the game on the other store already.
No. Steam Family Sharing is only useful for games on Steam, and even then only those where the publishers themselves decide to support it (more likely an opt-out than opt-in).
SFS cannot allow you to share an app you don't own on Steam, or an app that isn't on Steam, or an app that's on Steam but doesn't allow Steam Family Sharing.
You may have gotten confused with Steam Link, which can be used to remotely play games and isn't limited to just Steam.