Hearing Protection, eye protection, extra magazines (I'd recommend having at least 4 total), a cleaning kit, a discrete range bag to hold everything along with the extra ammo and a safe. Also a good holster if you plan on conceal carry (check your local laws around this) I personally prefer appendix carry but there are a lot of options here. Some guns will allow you to mount a light which can be nice for a home defense gun but I find them a little bulky for carry. However, I usually have a flashlight in my pocket and there are some good grips you can utilize: https://www.usacarry.com/flashlight-shooting-techniques/ with a standalone flashlight.
Optionally they have things that will make loading magazines easier which is optional but they are usually pretty inexpensive and if you plan on a big range day, they can just make your life a little easier. It's absolutely not required and you can wait on this and see how easy/hard it is to load your magazines before getting one.
If you have a range near you that lets you rent guns, that's the best way because you can try a few and see what you like. However, be warned, some places won't let you rent if you go alone because too many people have committed suicide that way so before you go, check their policy on that, sometimes you just have to bring a friend.
As for what gun, there are a lot of really good ones out there. Expect to pay about $400-$500, unless you can find a good deal on a used gun. (some places will have police trade ins which can be had for cheaper) If you can find a local gun store that is LGBTQ+ friendly, that's where I'd go to buy it (which might be easier than you might think if you're in a blue state) but before you go, you can browse around sites like https://www.gunbroker.com/ or https://www.armslist.com/ to get an idea of what might be available and about what the prices are currently. If you wanted to order from an online site, you'd still need a FFL so finding a good local dealer is still important.
I'd recommend 9mm, it's a good balance of stopping power, and being able to hold a reasonable number of rounds without being too heavy. Also I'd recommend a Semi-Auto over a revolver, they hold more rounds, are easier to reload (with extra magazines) and if you get a decent one, are generally just as reliable. Glock has already been mentioned and they are certainly a good brand but I'd also look at Smith and Wesson (S&W) (specifically their m&p line), Ruger and Walther. There are other good brands as well, but I'd start there. On the upper end, if you wanted to spend a little more, I'd also take a look at Sig and Heckler and Koch (H&K).
Finally, I'd recommend getting some training. ESPECIALLY if you are going to conceal carry but also if you are just looking for home defense. I'd recommend starting with https://www.pinkpistols.org/ and see if there's a chapter near you but you should have some option.
Live the 4 rules: https://www.corneredcat.com/article/firearms-safety/the-four-rules/ and get out and practice!!!
This is sure to help food prices go down! /s