Literally nothing seems to be working for me

Hello friends, today I'm here to show you all the amazingness I've crea- wait...

So when I export my mods, whether it's a block, fluid, food, or anything else at all, when I open Minecraft, they appear to be untextured and do not function the way they were intended to. I was making school style lockers, but all I could do was place them, and I couldn't open their storage at all, and I made a drinkable food, but I could only hold it in my hand (and of course, throw it).

I'm honestly not sure what I should do, and I feel like I should switch to another software that is more easier to handle and doesn't have as many errors for people than this does. Please, someone help me fix this.