Greetings and welcome to our happy gathering.
Rich (RWAP) was pointing you to our Wiki which you can find on
http://qlwiki.theqlforum.com which has masses of useful information about the QL and its cousins, and the SBASIC/SuperBASIC Reference Manual which is also online (and can be downloaded for offline perusal) at
https://superbasic-manual.readthedocs.io/en/latest/. Both are open to be updated if you happen to have some information.
If you are interested in Assembly Language, then feel free to help yourself to my book on the matter at
http://qdosmsq.dunbar-it.co.uk/download ... sembly.pdf as well as a few little "slightly irregular" QL Assembly eMagazines at
http://qdosmsq.dunbar-it.co.uk/download ... ge_001.pdf,
http://qdosmsq.dunbar-it.co.uk/download ... ge_002.pdf and (finally)
http://qdosmsq.dunbar-it.co.uk/download ... ge_003.pdf. (Unashamed plug!

).
There are a lot of knowledgeable hardware people on here too, and they don't mind answering questions!
If you wish to download the entire SBASIC/SuperBASIC online manual, then go to the link above, scroll down the page to the bottom where on the far left you will see "Read the docs" and a down pointing arrow - click it. On the window that pops down, click PDF, EPUB or HTML to download the desired format.
If you are looking for software, well check out the Sinclair QL Homepage where just about everything (legal) is available - more being added almost all the time too. That's at
http://www.dilwyn.me.uk/.
Have fun!
Cheers,
Norm.