You also need to have minimum 17" wheels.
EDIT: So IF YOU ARE ON 16s NOW, and need to upgrade those too, you NEED TO reevaluate doing the 2020+ 4 piston calipers. Those require at least an 18" wheel, and not all 18" wheels will fit. Those are a better caliper and if you are buying everything to do it anyways, then you aren't spending that much more, and you will want to just do it once. I'm not telling you to do it, but you do want to spend the time to price em both out, see what kind of wheels you want to have, and compare your two overall options. If you don't have the wheels yet, then what you need to get is to similar to not be aware of your options before you start buying parts.
If you need to do the wheels (which is also tires), that's the biggest cost of this. If that's not immediately in the budget, then I would highly recommend the hydroboost swap. It will definitely improve your braking, and your overall driving experience and confidence in the mean time until you can come across a good set of take-offs, or a better time to upgrade the wheels and tires.
You could also buy new pads for $30-$50, (and make sure you have clear brake fluid) to improve what you have now.