I’m just starting out in dnd and creating my first character (a half-elf wizard) and I’m at the equipment section. I’ve looked up the differences between the component pouch and arcane focus and can’t decide! Should I chose the component pouch because it’s more expensive and therefore harder to get later? Should I get an arcane focus and have it double as a quarter staff so I don’t have to keep track of as many things? Should I just buy a cheap sack thingy instead of the component pouch? Is one easier to use than the other? I don’t know!
It doesn't matter very much, certainly not for ease of play. Pick the one that you like the best
Each item has the same primary function as far as spellcasting goes: they abstract away the need to manage an inventory of common material components for spells. If you have either one, and a free hand, you don't have to worry about having a material component for a spell (as long as it's not listed with a monetary value)-- you're either assumed to have that component (component pouch) or you bypass the requirement (arcane focus).
If you have neither, then you have to have the specific item in your inventory to cast the spell (as would be the case with a cheap sack). This is more limiting and can be awkward to work with, primarily as you need to do more inventory tracking of items that have no other purpose. Without a monetary value they can be tricky to shop for, and even if you want to forage for them that requires some extra scenario work. There is no mechanical upside to taking this route, and there is (generally) no reason not to take a component pouch or arcane focus at character creation.
As in the question linked in comments, there are a few edge cases where one might be better than the other. If you multiclass into another spellcasting class besides Wizard, an arcane focus might not work for both (such as Wizard/Cleric, due to limitations on what a holy symbol can do, or Wizard/Ranger, due to class restrictions on arcane focus use and non-overlapping spells). In such a case, the component pouch is more useful.
Depending on what the arcane focus is, it might be useful in some other capacity, such as a quarterstaff as a weapon (or an arcane focus you're likely to already have in hand!). But these are very specific, not terribly likely to come up, may not apply to your character, and are things that a DM might be variably flexible with in any case.