You can learn more about BASIC programming from YouTube and Wikipedia.
During the 1984/85 school year, I had to take an advanced BASIC programming class in 10th grade on APPLE 2 (green-screen beep-boop noisy floppy diskette drive) computers.
Check Danny's thread 'how do you make games'. I answered it over there. Nowadays, there are virtually no colleges teaching BASIC or any offshoot of it. So yeah, I would read the sample code and change to see what it does, read the pdf from their website, and reading the built-in manuals. Don't be discouraged if you're stuck.
