Is there a machine in Home Depo that will cut blinds, and a person who knows how to do it?

They do, however only a select brand/type can be cut.

I am unsure.

Yes, I've had them cut blinds several times for me.

Absolutely, and it's free

Yes

Yes, and they can install the blinds for you as well.

Yes they most definitely have one. It's whether or not they have someone on hand that can use it.

They do have one. You'll be lucky if it's not broken.