I learned to type when I was a kid (in Flanders), around the year 1985 or so (on a purely mechanical typewriter) and we learned to type two spaces after a perio

I learned to type when I was a kid (in Flanders), around the year 1985 or so (on a purely mechanical typewriter) and we learned to type two spaces after a period. Also I never learned to put a space before colons etc. I feel like I know the rule is to not do that, but I'm not sure where, if ever, I learned that rule. In Belgium we use the same AZERTY keyboard layout with France (largely) but apparently the typographical rules vary widely.