Switch with 2 black wires and 1 white

Make sure the black wire going in the backstab is connected to the backstab closest to the screw terminal with the black wire. I am assuming this is the case, but we can't tell for sure without a picture.

Whoever wired this originally used a white wire for the hot pigtail. This small length of white wire connects from the wire nut with the black wires to the switch. Put some black electrical tape on this wire so it won't confuse anyone, or better yet, replace it with a 6" length of black wire of the same gauge or bigger (likely 14ga).

This original pigtail goes to one of the screw terminals on your switch. The other two black wires get put into a new wire nut with another new black 6" wire pigtail. This new pigtail goes to the other screw terminal on your switch. Unless you have a metal box, you should run a ground wire to your new switch's ground screw also. You might need yet another wire nut and another ground pigtail to connect ground to the switch properly.

When you post a picture we will be able to verify this is correct and give you additional advice if necessary.

This may not be the ideal solution but I did get it connected an working. I did not realize that I could put more than one of the wires on a single screw on the switch. Once I figured this out, I simply connected the formerly backstabbed wires to their corresponding screws and doubling up on the screw that already had a wire on it.

Thanks for the help, and if you have suggestions on making it better, let me know.