Random files keep popping up when I use banking app or other apps

Did you give permission for the app to save files in the Files app? If you did, you should see it listed at Settings > Privacy & Security > Files and Folders. It is up to the developer of the app on what files it stores there and for what purpose after you have given them permission. You can contact them for additional info or what effect it has on using the app when you revoke permission for Files access.

GhostGlow91 wrote:

I did that, but it still popped up.

If you revoked permission for the app to store files in the Files app, it will no longer store files there, but does not automatically delete the files. If the bank said they are just cache files that does not affect using the app, then delete them.

No, you do not have a virus, malware, or spyware. If that is your only concern, there is no action needed and you can continue to let the banking app store data in your Files app.

Delete the Renasant app (find it by searching if necessary)

GhostGlow91 wrote:

I did that, but it still popped up. People I asked in person said it was just cache files. I’m more worried about the phone having a potential virus. My phone hasn’t been jailbroken, no random apps added, it’s not heating up, battery is fine. I just downloaded a mp4 video and just worried it had a virus after I learned about the potential threats. I did factory reset my phone as well. Just worried.

There are NO viruses which can infect an iPhone, unless the phone has been jailbroken. I'm assuming you wouldn't know how to jailbreak your phone, to begin with. So there is no need to be worried about a virus, which doesn't exist.

Many apps store data in the Files app, if that app is ok then its fine.