I'm learning how to use Realband on Windows 10 to record live instruments and vocals on to tracks. I'm using an HP Notebook model 15-db0048ca and a new Focusrite Scarlett Solo V3 interface unit, the one with the new "AIR" button on it. Previously I was using a Fostex MR-8 recorder machine to do recording, then transfering the recorded WAV files into my Windows 10 laptop and importing them into the free 16 track KRISTAL audio engine application, so I wasn't actually recording ON my laptop. The BIAB/REALBAND tutorials that I looked at didn't really give me the very basic startup information I needed to do that kind of recording.
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I found an experienced user who helped get me started. He set up my drivers as below:
FOCUSRITE SCARLETT SOLO DRIVER SET UP IN REALBAND...
Options > Preferences > 2 Audio tab ...
Audio Driver Type: select MME (this driver seemed to work best for me, (started with little probs)
Drivers: Click on the "Drivers" box to see the available selections.
Under the Audio Input Drivers, select "Analogue 1 + 2 (Focusrite Usb A..."
Under the Audio Output Drivers, I selected my laptop's own "Speaker/Headphone (Realtek High..."
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Once the above settings were put into place, I was able to record through my Focusrite Scarlett Solo V3 interface.
I put my RealBand app into the "Tracks" view by clicking on the "Tracks" icon in the "ALL TRACKS" section at the top of the RealBand window; then arming a track by clicking on one of the track numbers along the left side of the tracks; then clicking on the round red "Record" record button along the bottom of the RealBand window. Basic, basic stuff that the tutorials I watched didn't tell me. My mentor also showed me how to move a recorded track to the left or right on the time line by selecting/high lighting it then, while hold down the control (ctrl) key, dragging the recorded section to where I wanted it. He also reminded me that I could shrink or increase the viewed track timeline by hovering the cursor over the tracks and rolling my mouse wheel each way. I think I finally can get started using RealBand with that simple lesson. :-)

Windows 10 PC, Realband, using a Focusrite Scarlett Solo interface