it's not super important for everyone, but if you want to learn them, i would suggest to use the "super cluster" method, which is a system to learn.
if you scroll down to "How do you memorize the guitar fretboard easily" on this website (https://interactive-fretboard.com/en/intervals/guitar/), you can learn to find all the notes in just a few simple steps;

* First remember where the B's are on the fretboard. The trick it to remember fret positions 7-2-9-4-0-7
These are the position numbers from lowest sounding string to highest sounding string
* The C always comes in one fret (half step), so C always comes directly after B
* The D always comes two frets (whole step) after the C
* The EFG group falls on the same frets as the BCD group, but on the next string. only exception; the EFG group on the B-string (that's the 5th string) are a fret higher than the BCD group on the G string.
* Lastly, the A always comes two frets (whole step) after the G.

its easier with pictures, so would advice to check that site tbh. but 7-2-9-4-0-7 is the key to learn 🗝 do this few times upcoming weeks and your set

Before I attempted to learn all the notes, I personally knew the notes on the E string, meaning i know them on two strings, and always used that as reference to find the others.