TikTok app downloaded w/o my permission

TikTok app download somehow on my phone. Now when my sister sends me a TikTok video instead of sending me to the website it opens the app. I go to the app store and search for TikTok and its says "get" instead of open. I look in the Home Screen and do not see the app. I swipe to the left for the App Library and type TikTok and there it is. I try to grap it from the library and put it in the Home Screen and it disappears. I then tried to look for it in my settings and it's not there. I checked in "Screen Time" and under "Content & Privacy Restrictions" and then "iTunes & App Store Purchases" and I have "Deleting Apps" set to "allow." I tried deleting directly from the Library and it gives me the option to "Remove App Clip." Anyone knows what an "App Clip" is and how to avoid them in the future?