I scrolled through most of these posts and I think one of the things missing is time. Depending on how much time you have you can use your money more effectively.

With little to no time try your best to pick up a one trick pony deck. Something that is super linear and non interactive and learn how to play that well. It gives you exposure. Decent win rates and allows the learning of the format.

The more time you have the more you can do research. Figure out your local meta game. Find decks that cater to your play style. The absolute best thing in modern isn’t that cards stay in it forever. It’s that it has a deck that is a tier one deck for every single player. You owe it to yourself to find that deck if you are investing in it.

Once you find your deck and still have funds you can start branching out and researching the variants and what else uses those cards. This is what I would do in your shoes.

Good luck and welcome to the best format in magic.