>>50377189pick a favorite pokemon
hopefully not charizard, umbreon, rayquaza and collect all or many of its cards. bulbapedia is a good resource for this
from that you'll learn about what other sets, artists, styles etc. you might like
for storage, use sleeves and then either toploaders or a side-loading binder (like vaultx, card guardian etc.). ultra pro penny sleeves are great and cheap; my favorite nicer sleeves are dragon shied dual mattes