Marking, selecting, editing tracks

I’m a noob learning by trial and error how to select sections of tracks, how to set markers and use them, and trying to figure out how to punch in. Running the Android version on a tablet.

Can anyone point me to resource(s) that explain this in detail? All I can find are a few seconds on n-track’s many 1-minute videos, and half a manual page.

There are a number of little red marks that show up in the timeline, and 2 blue arrows that seemingly appear at random (very useful but I don’t know how to make them appear). Also 2 widgets that show up at edges of a selection that I’d think would let me shrink or expand but don’t seem to do anything. What “splice” really does. How to quickly make the play position jump to the various marks. All this kind of good stuff, and I’m sure a lot more.

I’m managing to punch in through laborious selection and copying of track sections, but it’s clunky and I suspect there are much better ways I could be doing it.

Just watched a new video on the piano roll. It was 5 minutes long and taught me SOOOOO much. I’d really really like one that addresses the questions I have above, and then some.

THANKS!
Jon