Recorded gameplay becomes choppy then crashes

And past the previous excellent comments, use the mov recording option in OBS. Do not use mpr from OBS for editing. Yuck.

There’s a big difference between an app that plays media and one that edits it. Premiere Pro requires significantly more resources from your computer than a simple media player.

It sounds like your computer might be struggling. To help pinpoint the issue, it would be helpful to know your computer specs and the codec you’re using to record in OBS.

In the meantime, I strongly recommend looking into editing with proxy files. This can make the editing process much smoother by using lower-resolution versions of your footage during editing. You can learn more about proxy workflows here: Proxy Workflow in Premiere Pro.

Exactly what is INSIDE the video you are editing?
Report back with the codec details of your file, use the program below
Free program to get file information for PC/Mac http://mediaarea.net/en/MediaInfo/Download
- a MediaInfo tutorial https://youtu.be/Ivy9ckSX1M0
- when you analyze your file in MediaInfo and post a screen shot in the forum, do so in TREE view
- post your information IN your message, not as an attachment that someone would have to download
.
Does your video use a Variable Frame Rate? See https://community.adobe.com/t5/Premiere-Pro/Variable-frame-rate-video-with-Premiere-Pro/td-p/4601935
If yes, use https://handbrake.fr/ open source transcoder/converter to convert to Constant Frame Rate
Handbrake tutorial https://www.youtube.com/watch?v=xlvxgVREX-Y&t=34s