You can use Final Cut Pro on an iPad using Apple AirPlay/Sidecar with a MacBook Pro. It isn’t actually installed on the iPad, but here the iPad basically works as a remote touch screen monitor. This is useful for editors on the go, but you will need to have your MacBook close at all times, and all files will be stored on the macbook. 

If you want to edit videos on your iPad with native apps (no Macbook required), you can use the iPhotos app for basic video editing (Crop, Trim, Rotate).

There are many video editing apps in the iOS app store. For more advanced features we recommend: 

iMovie – $4

Premier Rush – Subscription

LumaFusion – $28.99