I got to looking at the subpanel I bought, it's a Homeline 100 Amp. There is only one ground bar in it and it connects to the panel box by a screw. Do I need to get another grounding bar for the neutral and keep it isolated?

o, you need a separate bar and call it an equipment ground bar, bolt it into the metal box using the threaded machines screws that come with it into the threaded holes already in the panel.

And remove the connection screw from the neutral, the neutral bar will now be isolated for all white branch circuit neutral conductors. Use the equipment bar for any green or bare wires.

I think I have the info needed and you have been an immense help tkrussel. I'll pick up the wire, breakers, antioxidant and ground bar tomorrow at Lowe's and get it wired up. If I run into any other issues, I'll post and look for your answers.
Thanks again!