Importing from .obj model purple and black and uncentered?

I am a beginner at MCreator but even one of my friends who uses MCreator alot said he doesnt know how to fix this, I have tried as much as I could, anyone know a solution?

Ive made the model in blockbench then turned it into one polygon (as said in the instructions thing) in blender, ive confirmed that the uv mapping is correct, but the texture isnt visible ingame

(This is a trophy im making btw)