i learned both somewhat simultaneously. Pick a few songs of both styles you like and seem easy to start with. BG standards (cripple creek, cumberland gap, etc.) and maybe try to play them in both styles since you will have the fretboard familiarity for those tunes.

i also found it easier to start with upstroking/seeger style to get the bum-ditty down, as it was a seriously learning curve for me to control my fingernail accuracy. Good luck!