all bulbasaur pokemon cards Pokémon TCG Reveals Pokémon Card 151: Illustration Perfect for collectors and enthusiasts. Bulbasaur Pokemon Card Credit Card

Colorless energy symbols in attack costs mean you can attach any sort of energy and other symbols (let's say fire for instance) mean you can only attach an energy of their type.

Captain Lannery Storm and Goldspan Dragon can get you the Treasure tokens you need while Falkenrath Celebrants and Blood Servitor can give you Blood tokens

Yes, through MTG Arena and physical boosters

Cards like Vizier of the Menagerie and Agatha's Soul Cauldron that let you spend mana as though it were mana of any color count as mana fixing, but they're not really mana filtering

Trelasarra at 21 cents is the cleanest on-ramp

Hopefully these will inspire you to try out some new decks with Kaldheim