for creativity's sake youre probably best off not knowing anything, "jamming out and screwing around" are where the interesting stuff comes from.. the only thing ive found it useful for is communicating faster with another musician... who also has to "know theory". that said, there is a metric quadrafuckton of theory books out there.. probably best to go to library or used book store than doomed forever forum!
here's a couple of very very basic tips.
-surprising amount of people dont know that the fretboard "starts over" on fret 12
-keep in mind that there are only 12 notes in the western chromatic scale and the key or mode youre playing in will often use less than half of them
-also keep in mind that of these notes and the 144 possible fret positions around 120 (not going to do math lol) of those notes can also be played in the exact octave somewhere else on the fretboard.
hope this can clear some creative clutter, sorry if it's nonsense or basic shit.
bonus: an open strummed guitar in standard is an E13th chord. tell your friends.