Can two users play the same game on PS4?
You can play games together or share your game library with friends and family members who are also still using their PS4, thanks to a feature called Share Play. (If you do have a friend with a PS5, you can also play their PS5 games on your PS4 with Share Play, too.)
How can 2 players play on the same PS4?
For example, if you have other consoles in your home and other people want to play the same game with you using those additional consoles, each console must have its own copy of the game.
Can two people play the same game on different consoles?
If 2 people are using the same steam account, no. A single steam player can only play one steam game at a time. If 2 people are using their own account, thus 2 different accounts, then yes. Each owns their own copy of the game.