Why is a texture not showing on an object?

First of all, I’m a complete beginner, so sorry if this is obvious. I want to create a video where a camera slowly zooms out from the door of a balcony. I downloaded a premade .obj of the door, but the only decent premade balcony I could find came as a full blender project which has a fair amount of stuff on it I don’t fully understand, some of which is probably the cause of the problem. When I import the door object and give it a texture, it doesn’t appear, but if I do so in a new project it works perfectly.

I’d suggest you take the time to learn Blender. Then you can ask relevant questions. ATM, your title question is too vague/general/unfocused to answer.

Thanks. The problem with that is I really just need it for this one thing. I’m a film editor, just can’t find any archive footage for a shot I need for a project. Really would rather not have to spend that much time doing that much learning for something I’ll probably never use again.

you need to UV unwrap it if it isn’t already. or just set it to triplanar/box projection and hope for the best

Perhaps you should consider posting in the jobs forum on here.