[DarkStar]

I would not try to read it all the way through - just look up topics when you need too.

When a media item is imported onto an empty track, the track name is derived form the item name.

To rename the track (and in the Mixer):
-- double-click the track name.

What do you want to delete when you say "section"? Part of an loaded media item? There are several ways - I would probably split it twice:
-- position the edit cursor by clicking in the timeline above the tracks, then press S.
-- repeat as needed.
-- select the part you don't want and press Delete.

You can turn off Snap for precise position of the edit cursor and zoom in to make sure you position at a zero-crossing.