Some of my apps disappeared such as tiktok, Instagram, twitter and even AppStore and Camera

My apps disappeared and are "uninstalled", yesterday I was watching tiktok and out of nowhere the app closed, when I see the home screen there were no tiktok and other apps, I tried to reinstall them from AppStore but oh surprise, AppStore is not there either. I have tried several things but my apps still do not appear, and the funny thing is that some such as camera and AppStore appear as installed when I enter settings, but they do not appear in the start or in the search engine