I'm a personal trainer and I am designing programs in Excel to make my job easier. I pretty much am teaching myself how to use Excel but I can't figure a couple of things out. the programs I am designing I want to give to clients so they can use themselves but I don't want them to delete the formulas in certain boxes by accident. How can I make an Excel program functional to use but yet make certain cells locked so they can't be deleted by accident?

P.S.

I know you can lock an entire document, but I need the document to be functional and parts of it to be locked.

Thank you that helped me a ton