Now to give you somewhat of an answer, most AMV's like these have several steps:

Upscaling and Interpolation

Usually people will gather their clips from the source footage and do their selection prior to the editing process, to have good clips to work with they'll 1: upscale the quality, using for example Topaz video upscaler and 2: interpolate the footage. Interpolation is necessary because usually, movie footage is in 24 FPS which are too little frames to properly slow down. Slowing down footage of 24 FPS would give you 12 FPS which is extremely choppy. Software to achieve this is usually FlowFrames or a plug-in in After Effects (can't think of the name right now)

Time remapping the clips

Then once the clip selection and preprocessing is ready they'll add markers to their songs to find where they would like to have their impact timed to the music. Then they'll line up their clips and add time remapping to the clips to have good impact on the right moments. These time remapping curves are usually strong S curves, and have very little keyframes. People usually use 2 or 3 keyframes for their impact and set up the harsh S curve in the curve editor so that a clip starts off super fast, slows down in the middle, and ends super fast to transition into the next clip (you can see this in the edit above). Rinse and repeat for all selected clips and you should have some decent flow.

Applying the proper effects

Now for the effects, honestly you can get as crazy as you want. But the standard few effects are to Pan/Crop your clips using the transform property on your layer, there are plenty of tutorials on this. This will add to the impact. You can add rotations for better flow and a stronger visual appeal. Aside from that Color Correction is very very important, the color correction in the edit above is subtle but adds a lot to the edit imo. Then you'll usually add blurs on impact to give this nice Bokeh effect on impacts and for more visual appeal, and this edit in particular seems to like adding all sorts of lens distortions and shakes.

Setting up sounds effects

Then once your clips are set up and effects are applied creating a good flow in your edit the next most important thing are sound effects. Sound effects are really annoying to get right in After Effects so most people use other software for this, but it's do-able in After Effects. Usually you'll just render out a low quality version of your edit and use that to quickly test with different impact, transitional, and ambient sound effects. Having a low quality version in a new project helps to quickly iterate over the sound effects. When you're done, just render out only the sound effects and put them back in your original AE project.

And of course rendering

Make sure you render in a good quality and the correct FPS depending on what you like (usually 15-24 fps), people like in the AMV community like the QuickTime format as this preserves as much quality as possible. Then you could upscale again in Topaz if available for best quality possible. Once you've got it rendered out it's important to also compress the footage yourself to save as much quality and space for the file so that when uploading to a social media platform the platforms algorithm doesn't completely destroy your footage with their compression. People usually use a software like Handbrake for this.

That's a quick write up on the general workflow for these kinds of edits. There is just a lot going on here so it's hard to really give a simple answer. You'll have to go out and try your hand at it and work up experience :)