Questions in Game Dev

I am making a DDLC (Doki Doki Literature Club) Mod and I was wondering if anyone had any pointers? Any and all help Is greatly appreciated as this is my first time making a mod or anything of the sort!
What the code for a moving a charater in 2d mario fasion...
would html be a good progaming lanuage for future games
Can i get some help from other developers out there so i can make a new game .
i am building a firework generator (a game where you build your own special firework) https://gamejolt.com/games/firework-generator/456994
should i...
I am looking for people that know how to code GML. I am making an Undertale fan game. There is only one coder and that is me. I will provide full credit in the game. I will accept people of any skill level. Please LMK in the comments and I will get to you