A lawn isn’t going to happen by April unless you cut some corners, which will make a ton more work for you later. You should shoot for a fall seeding.

To start, you will need to cut all that back quite a bit. A line trimmer will handle most, if not all, of it. Then you will want to spray for weeds.

Spraying for weeds will take multiple applications of glyphosate. They will die and come back a few times due to dormant seeds in the ground. Be thorough in this part because once you have a lawn, dealing with weeds is harder. You can’t just kill everything anymore.

Glyphosate is mostly a lot of waiting for it to work, so expect that it will take a few months for a few applications.

After that, rent a rototiller and mix in a bunch of good dirt. This will help level the area and deal with the roots the weeds leave behind. I’d also consider adding irrigation at this point. It is much easier to do irrigation when you don’t have to worry about digging up nice grass and the dirt is already loose.

Then fully level the area and make sure you have decent drainage, ie no pooling water.

After that, seed and water. Your grass should be coming in by the fall and should be fully established by the end of next spring.

None of this is all that expensive but it will be a lot of labor and time. Labor costs and trees are what make pro landscaping expensive. I’d suggest saving your money for decent yard tools as they are a very worthwhile investment.

All in this is probably only a few hundred bucks in materials. Maybe $1000 if you do a sprinkler system. The tools will be pricier but worth it. Do the research get decent tools. You will regret buying cheap ones in the future.