How to play games without internet with Steam offline mode?

To play games without the internet with Steam offline mode you must first prepare your Steam account for this, and then enable the feature. 

Steam (service) - Wikipedia

How to play games on a Steam Deck in offline mode should you

You Can Play Many Steam Games Offline — Here's How

Steam Community :: Guide :: GTA IV: Complete Edition: How to Play

Can i play offline without the server issues? - Menus & Activities

5 Best Offline PC Games You Can Play Without Using The Internet

Can i play offline without the server issues? - Menus & Activities

11 of the best games you can play offline

How to Appear Offline on Steam (Even When You're Online)

FIX: Can't Connect to Steam Network Error