Simple instructions for how to use Geogebra

Can anyone tell me if there are any simple to follow instructions for functions in “Geogebra”? I don’t want to keep on using Excel, especially for more advanced work, but gave up on “Geogebra” before simply because I could never find simple, clear instructions about how to use the various functions. I spent this morning simply trying to find out how to input y=1000 x 1.020^-t and could not do it, using the spreadsheet function. The videos on “You Tube” are appalling. Do these people not realise that if they are recording something, they have time to decide what they are going to say and work out how best to say it? There is no excuse for “errrrr, uuuummmmm, oh I don’t know how to do that…” mistakes, poor volume control etc.
Very frustrating.

Recently I started exploring how Atom might integrate with Wolfram. Through queries.

Click here for your example.