Hi, your public profile is blank so I don't know whether you have other tools at this time. So I'm going to make a few suggestions for upcoming tool purchases assuming you don't have any of these tools.
First and foremost, a table saw. Once you have one, it becomes the center of your shop. There are many kinds of joints that require a table saw and a good blade or two. I was wathing seasons one through 3 of Woodsmith Shop on DVDs and realized they have simplified and focus on four tools. Router, of course, table saw, drill press and a band saw.
You'll always get this advice, always buy the best tool you can afford, even if it requires a little credit to move up. However, being real about budgets, give the Bosch 4100 - 10 inch jobsite saw. It gets top rating around here for a budget saw. Around $600 new. Add to that a Wixey digital angle finder to set the blade to a precise angle (90, 45, 22.5 degrees commonly. See pix.
I have and really like the bench model WEN 4214 12-Inch Variable Speed drill press. About $240 (less from some dealers), it is taller than the cheapo models in the big box stores, and you don't have to fiddle with changing belts around, it has a variable speed lever, and plenty of power. Interesting that it has exactly the same casting marks as the JET, which is far more expensive.
Rikon and WEN both sell the same small, 12 inch band saw. It is a bench model and comes with roller bearing blade guides. Very nice little saw. 72.5 inch blades are not expensive and you can resaw using the half inch blade if you feed the piece slowly. (Resaw means cutting thin strips from a wider piece.) I have a bigger band saw, but use the smaller Rikon far more often. I can't see any difference between the Rikon and WEN. They are identical. Cost is about $237 for the WEN, (https://www.amazon.com/s?k=WEN+band+saw&ref=nb_sb_noss_2
) and about $300 for the Rikon. The WEN comes with a stand, the Rikon doesn't. Get half inch, quarter inch and 3/16th inch plades to cover all uses. 3 or 4 teeth per inch for the half inch, finer for the smaller. Take your time making cuts in thick pieces.
If you are using decent (many layers) of plywood or dimensional lumber from big box stores, you will be able to make a lot of things with these basic tools. You'll want to be very careful to avoid pieces with twists, bows or other distortions. I often use pine 1x4s I get from Home Depot. I pick each piece after carefully looking for the straightest, most know free pieces, that lay flat on the concrete floor when laid on both edges. Chech for twists by sighting down the length to see if the closest end is more or less parallel, if not, no thanks. Sometimes I'll buy a piece that lots of clear length, but maybe a foot or two that isn't.
A great first project is making your own router table, using a sheet of very flat ply. Lots of discussion of this on the Forums, just search and you'll find them.
Personally, I'd add a couple of additional items in my starter kit. A GOOD QUALITY set of four chisels and a course, medium and fine sharpening "stone", I now use a fine diamond stone. Watch some videos on preparing and sharpening your chisels. If budget is tight, you can use 150, 220, 400, 800 and even 1200 grit sandpaper to sharpen instead of the stone. But you'l need something very flat to mount them on, such as a really flat chunk of plate glass or even a large, smooth piece of floor tile. Check for flatness with a good straight edge (ruler).
Another tool is a small block plane. You want one with a low angle blade. Sharpening is similar to sharpening a chisel. It is a fast way to ease a sharp, easily damaged, edge. As you build projects such as boxes or drawers, you'll find yourself reaching for your block plane. see pix.
Get a good combination square. see pix. Mine is 70 years old, so it will outlive you, so don't go for a cheapie. Get one with engraved markings. There is often a level and hidden in the "handle" is a small spike for making scribe marks. You can get 6, 12 and 18 inches. A 12 is most common, but I like having the 6 inch to tuck into my apron. About $50 for both in decent quality.
Last on my list is a Grripper, a plastic safety device for use on the router or table saw. Keeps your hands safe, and allows you to apply pressure down, forward and toward the fence. Best basic safety device there is. See pix. About $60.
Pictures are in whatever order they appear. Pretty obvious.