Hello radka112,
Welcome to Apple Support Communities. We understand that the camera, and app drawer are not functional within Messages app, and we'd be happy to look into this with you.
When did you first notice this issue? What happens when you tap the camera and App Store icons in the screenshot you shared in your previous message? Also, is this happening with specific contacts, or multiple?
To get started, please check this out:
Use iMessage apps on your iPhone, iPad, and iPod touch
Also, make sure your iPhone is up-to-date on software. When you navigate to: Settings > General > Software Update do you see any available updates? If so, please back up your iPhone, then update as explained in the following links:
How to back up your iPhone, iPad, and iPod touch
Update your iPhone, iPad, or iPod touch
If your device is already up-to-date on software, try the steps in the following link:
If an app unexpectedly quits, stops responding, or won’t open
Let us know if that helps. Cheers!