I have squirrels living inside my attic, I looked at the outside of my house and cannot see any holes how they are getting inside?
They are very clever at finding ways in. They will often make entrance holes in the space between the gutter and the the roofline and therefore they can be difficult to see.
Don’t block up holes until you are sure there are no young ones to be trapped inside.
The mother will tear your house apart to rescue them.