Hey horackoel,
We'd be happy to help out. Looks like you've got some apps offloading to save space.
When this occurs, this doesn't necessarily mean you're out of storage, it could just be that you haven't used those apps in awhile. Under Settings > General > iPhone Storage there would have been a recommendation allowing you to enable "Offload Unused Apps" to save space.
If you believe that you are low on storage though, you can confirm this by going to the same place (Settings > General > iPhone Storage). For more info, check out: How to check the storage on your iPhone, iPad, and iPod touch - Apple Support
This feature isn't for everyone though, as there may be apps you don't use frequently, but always need to be able to access at any given moment. If you don't want this feature enabled, you can disable it by going to Settings > App Store > Toggle off 'Offload Unused Apps'.
Additionally, with the app icons being missing, does this only affect offloaded apps? You can determine which ones are offloaded by the iCloud symbol and the down arrow. Since this began, have you tried restarting your device?
We hope this helps out.
Take care!