Electrical. I own a very old home that has the old "2 slot" outlets. The house is so old that it

Question

I own a very old home that has the old "2 slot" outlets. The house is so old that it has 's***w in fuses' not breakers.
I want to upgrade all of the outlets in the entire house. My problem is that when I opened up one of the outlets, I don't see where to ground the new outlets?

Can anyone help me?