In need of an experienced modder/maybe coder

I seem to keep running into new problems with things I am trying to learn. I've tried looking at tutorials but often the creator just skips ahead a few folders/locations and I instantly get lost and confused.

If you manually edit the code in mcreator do you need to download anything else? ( Other than Forge/minecraft/blockbench/mcreator ). I am willing to learn the basics of coding to solve my issues but I need a more personal guide rather than a generic youtube video.

Just a few of the things I am trying but can't figure out ( maybe it needs coding? ): Better animation movement, for example one of my custom mobs back legs move in a rather comedic way which was not the ideal result. I also have slime mobs that I want to make jump instead of sliding around the floor. Another being making larger structures than just 16 by 16 due to chunk loading issues.

So pretty much if you know the answers/are able to be used for more questions/ simplify the steps/coding for a very new modder either let me know here or feel free to send a message ( assuming you can do that on here lmao )

Edit: Also with the next minecraft update coming out I assume it needs the next forge version. Since I am new to all this I have no idea how you go about updating mods