First, consider this: You are looking to restrict, protect, limit your data interactions with your user. If your user can see a table or datasheet, there is NO WAY to stop him/her from updating it. Therefore, you will have to do this through some type of form. Under no circumstances can you allow anyone to see the inner workings of your DB. Your users will work only through forms (and reports, of course).
You need to start reading on this topic: Securing a database.
The search feature of this forum (upper right corner of screen) can be used to find articles on that subject.
Now, the good news... IF you have a form covering everything for you, then you can very easily place restrictions on what can be done - including not only WHAT, but WHEN and HOW. The form provides a "scaffold" onto which you can build all sorts of tests, protections, safeguards, however you want to say it. Putting up this facade to hide your database's inner structure sounds difficult and for novice users it might be a bit daunting. But an unguarded Access offers NO control over what your users can & will do.