Hi Steve Zeeeee,
If you have a .webm file, you can trans-code it into MP4 using Handbrake software: https://handbrake.fr/ and import into Premiere Pro.
Note: Please use only with the files from sources that do not contain any kind of copy protection.
1 person found this helpful
If you wish to edit someone else's video, you really should be asking their permission and acquiring the video in a proper editing format. DNx and Cineform are both good options.
That's the ticket thank you. I should have known that. It's well within the fair use parameters.