I hope I'm following this, but here are a few questions:

Can Squibs sense the Fidelius Charm? Would it be able to protect them?

Squibs are able to hold careers in the wizarding world that don't require magic, correct? I'm just checking here, but they weren't eligibile for magical education?

If a Squib married into a wizarding family, would that be looked down upon? Would they be able to have magical children?

Sense they don't have a wand or magical abilities, what defences would they possess?

Basically, I'd like any detailed information about Squibs. Thank you.