Can you share steam games?

Like with xbox?

Yes google!

There's Steam Family Sharing, where you can share your game library with someone else. This other person can then access most of your games as long as you are not playing yourself.

There's family sharing, where you can share your library. However, only one person can play a game at a time - everyone else has to wait or play something else.

And now there's a new co-op mode. You can invite others into your game even if they don't have it and play with you, provided the game has such a mode.