The only difference between mold and mould is that mold is the correct spelling in American English, and in British English it is spelled mould.
This is true of the verb and the noun. As a verb, mold/mould means “shape something or someone” or “become moldy/mouldy.”
The noun mold/mould means the physical object used to form something (e.g., plastic) into a specific shape, or it refers to the fungal growth found in damp places.
The QuillBot Grammar Checker has selectable language regions, so you can always be sure you have the correct spelling of mold or mould.