Custom Fields Post Topic on specific categories

I know the question has been asked before but I don’t seem to find a solution so let me see if anyone canhelp

I would like to create a couple of fields on topics within a specific category.

2 fields to start off with, a Text field and an image upload field. I need the text field more than the image field but both would be nice.

Can anyone let me know how to go about this? I don’t know how to create a plugin but there is a guide I am happy to try and learn or maybe someone has a plugin already

Any assistance would be grateful please

I know there is an image upload button but I need a separate image upload just to clarify