I have been learning guitar myself for about a month and I am getting used to changing chords including barre chord and some strumming patterns (yet far from being perfect)

I have been playing multiple different songs usually whichever song I feel like during the practice .

However, the more I play, the more I feel I am not going to master any of those song however, I still feel I am improving.

I am not quite sure if I need to continue practice multiple different song or should "master" one song?

And how important is it to memorise the song from the beginning to the end?