Visual glitch when playing game

Godot Version

4.4.1

Question

I’m new to Godot, I’m following Brackeys video on making my first game. I’ve noticed that my game is very glitchy when playing and his is not. I’ve spent awhile searching for an answer yet I cannot find one.

New members can’t upload files so I uploaded a video to YouTube and will attach the link to the youtube video:
https://youtu.be/Z6o0FUuxWtc