permissions – Prevents the user from seeing other sub-sites

Is there a way to limit the number of users who can see other subsites that they do not have access to in site content or quick links?

Example:

The employee A = has access to sub-sites A, B and C. Should not see D / E / F

The employee B = has access to subsites D, E and F. Should not see A / B / C

I understand that if the user does not have permission to access a given site, he / she will access the page "Tell us why you need a access ", but the condition is to make it non-visible. (It's like we just want the user to know that these are the only sites available)