Respect to 2, don't you just look up at the start of the (gregorian) year when stuff is? I mostly do that in my country just to check when the holy friday holi

Respect to 2, don't you just look up at the start of the (gregorian) year when stuff is? I mostly do that in my country just to check when the holy friday holiday is, a few saint holidays, a couple of celebrations for the virgin mary, etc. Like, I know Easter follows a weird lunar calendar but I don't really calculate it.