Suit shopping

Since this is your first suit, I'd recommend the following:

1. A navy blue suit. It's more universal than a grey suit, and a better starting point from which you can build your wardrobe. Brands like Suit Supply, J.Crew, and Bonobos are going to be a little bit above your price range, but they are all high quality and will last you for years. Better to pony up cash now for a suit that will last a long time in your closet than spend $100 dollars less for something low quality that will last you no time at all - provided you take good care of what you buy in the first place. Make sure that you suit jacket is structured, meaning it has a silk lining in the back, which is the gold-standard for most brands. It makes the jacket warmer and more resilient to wrinkling, and gives it a fuller look. Unstructured suits are for the summer, and unnecessary until your wardrobe gets more developed. Any suit that you get from these brands should be well tailored already, hopefully with no after-market tailoring needing to be done.
2. I'd go with black shoes and a black belt instead of brown. Black is subtler and goes well with many many more things than brown does. You can wear a nice pair of black shoes with a suit, with simple slacks of many colors, and even with a tuxedo these days. I'd say for shoes, go Allen Edmonds. The price is high, but there is nothing worse than a pair of poorly made shoes. Again, if you treat them well, they'll last you for years. I just re-soled a pair of Allen Edmonds shoes that I've had for 6 years, and they look brand new, and will last me another 6 years. Any company that you end up buying the shoes from should also have an accompanying belt that you should purchase. You can also buy socks from the same company - I wouldn't go anything loud in that department quite yet, just black/dark grey/navy blue will suffice.
3. Purchase a few white shirts. You can go to a tailor and get yourself measured, and there are a host of websites (I, and my coworkers as well, buy from Charles Tyrwhitt) you can buy basically custom made shirts from. You can go with a bunch of collar styles, doesn't matter if it has buttons or not. Most people do buttonless these days - and if you do end up going buttonless, get a pair of plastic collar stays to keep your collar looking crisp. Charles Tyrwhitt shirts come with metal collar stays, but they're easily lost and it's always nice to have a few back ups.
4. Ties are the hardest part. They say the most about who you are and are your area for differentiation. Go for something subtle, though. You'll be an analyst, after all. You want 100% silk, and with a simple pattern. I'd recommend going to any mall (once this coronavirus clears up) and taking a walk through Bloomingdales or Neiman Marcus. They tend to have a larger selection of ties of superb quality, and if you look carefully some of them won't break the budget.

More than happy to expand on any of these if anyone has any thoughts. If I had to look back on my first suit, this is what I'd want.