Sharepoint 365 Folder Permissions

I have searched for a while but can not find an answer so thought i would ask the question..

I am trying to set up sharepoint so that at a top level i have:

Home directory with eight sub folders then each of those eight sub folders will have folders/ documents within them.

My question is can i grant everyone in the company permission to have access to the main Home folder then everyone can see each of the eight folders but when they click on one of the eight folders it only allows them into that folder (and its sub folders/ documents) if they have the correct permission levels?

Or do they only see the folders that they have access to?

Also when a user goes into one of the eight high level folders i want them to only have access to certain folders within the high level folder they have accessed. Is that possible like the above question or do they only see the folders that they have access to?

Thanks for your help!

Matt