Can't delete videos off 6s

I somehow got a bunch of computer programming videos on my phone. Iphone 6s. Now I can't figure out how to get them off. After searching Itunes for 20 minutes, I finally found "Home Videos" under "Tv Shows" "Library" in Itunes. I went inside it and highlighted all of the videos and removed from library or something... It was the only option for removing. (Just tried to remove some old music and it had 2 options to remove, however only 1 actually removed)

After deleting the files inside the folder, so to speak, the folder "Home Videos" disappears also. I think I'm home free until I check out my phone and find the the videos are still there. I even tried the restart my phone. I don't understand Itunes very well... besides it being more complicated the needed... The folder was in library, but I can't finder anything under "Devices" "My Iphone" as to where the videos would be stored. Movies and tv shows in my phone on itunes, is empty.

Now on my phone, I can go to settings>general>storage I can see the TV app is using about half a gig of data. I click it and I can "Review iTunes Videos" Save up to XXX MB see all downloaded videos from itunes and consider removing them. Click that. Then there's about 1.5GB... not XXX MB. I can very much click edit and delete them from there. The problem is I have to do it 1 by 1 and there are probably a hundred or so of them... If I go into the TV app I can see them and watch them, but it doesn't seem like I can delete them from there.

How do I delete these videos off my phone, easily/fast?