Difference between 15 vs 15A Receptacle and Wire size

Hello all,

On homedepot website, the receptacle is of 15 or 15A.

Question 1> What is the difference between 15 and 15A? What is better for residential usage?

Question 2> How do I know the correct wire size allowed for the receptacle?

For example:
Leviton 15 Amp Duplex Outlet - White-R52-05320-00W - The Home Depot
Leviton Model # R52-05320-00W (2) 15 Amp Duplex Outlet - White

I searched the specification but I didn't find the wire specification. What I am looking for is whether the receptacle accepts #10, #12, #14 wire etc.

Thank you

Difference between 15 vs 15A Receptacle and Wire size