How I make my videos! I have a YouTube channel. If you are smart you would know that by now. If you aren't I'm impressed how bad you are at listening. Cmon people! I tell you all the time!
First of all you screen record a video of any cool animation of your choice. I like WWII so I'll find some animations from war thunder ,world of warships, world of tanks and IL-2 sturmovick.
They all allow us to do this stuff so it's fine. If you want videos from videogames like those you might wanna find trailers. They have animation that look 10 times better than there gameplay. Never use gameplay footage for the videos. It looks ugly. then round all of the videos up with the music of your choice and bring it to your editing software. I use kinemaster. It's really good.
But anyway when editing make sure stuff match with the music if you're Luke you don't even have to do that stuff. But that's unlikely. Once you are done matching the music with the video export it out. Then send it to YouTube and enjoy!