how can i recover my apps with icloud if my iphone gets too damaged to read the screen ?

Apps themselves are not stored in iCloud or your backup. You will need to re-download the apps from the App Store.

Redownload apps and games from Apple - Apple Support

Where the data associated with those apps is stored depends on the app. Once you download Snapchat, for example, again, log in using your Snapchat account credentials. If the data is stored on Snapchat's servers, you should be good to go. If it's not, contact the app developer for more information.

You can backup your phone to your computer before your phone dies.