As Josie said, a real toe-tapper. I enjoyed the listen!
About the background vocals: one of the nice things about DAWs is being able to edit audio instead of having to re-do a bad take. So if you find you're coming in at the wrong point, you can shift the audio so it lines up correctly.
In my DAW - and Studio One,
I think - you can
click on an audio clip to select it, and then
drag it where you want it to go with the mouse.
But... typically there's something like "Snap To Grid" that automatically aligns the audio clip to 16th note (or larger) increments. To move the audio clip without it "snapping" in my DAW, I can hold down the
Shift key while dragging the clip. I think it works that way in Studio One, too.
Thanks for posting!