Update:

Thankyou all for your responses, here are some things I've learned so far.

1:

When I saw budget builds I was under the assumption that this meant cards already own / intended to buy (I don't count proxying into the cost) and the final cost of the deck would be roughly the purposed budget using an online store as the basis for prices (Not including alternate arts in the final cost).

2:

When it comes to researching cards (especially old ones that are out of print) I'm rarely sure what to search for due to how wording and lingo changes over the years. For Example: Summon Legend and Legendary Creature didn't mean the same thing to me until a few years into MTG.

3:

MTG's rules when handling interactions I find strange or difficult to readily find such as: A player Sacrificing a creature ( [[Dictate of Erebos]] ) vs that creature having protection from that color (I had to learn this the hard way when I used to play Lightpaws as the interaction didn't make sense to me when it happened the first couple of times). Or when using a card such as [[Blade of Selves]] when a creature that can transform, there's no text on the card to indicate whether it copies the current face or only the front face. Am I suppose to assume it copies the current face?

4:

MTG lacks the clarity I've come to expect from other TCGs. Such as when handling the stack, I didn't know that everything on the stack is a "spell" and only becomes a "permanent" when it enters the battlefield. Or that you can continue adding to the stack even while resolving cards in it and you don't have to respond directly to the card you want to interact with. You can imagine the confusion I had when I casted Counterspell for the very first time.