Just Tell Me What To Buy

Gi:

If this is your first gi, make sure it comes with a belt and buy a traditional color (white is preferable but blue is also acceptable). It is good practice to always have at least one white gi. As of this writing, this is the cheapest BJJ gi available and many students use it.

https://www.amazon.com/Jayefo-Brazilian-Lightweight-Preshrunk-Submission/dp/B07YCXV9HX

Some prefer to spend an extra $10 for a women's sized gi. Many use this one. Make sure you use the female sizing guide.

https://www.amazon.com/dp/B0839H7WVM

If you're tall or long-limbed and need a "long" size then it's a bit trickier; you'll have to do some digging for deals. Amazon always has upstart gi manufacturers selling in that $50 price range and many offer long sizes.

Rash Guard: 

Optional but many prefer to wear these tight fitting garments under their gi or for no-gi training. If you buy a "ranked" rash guard, make sure it's your current rank. Rash guard sizing typically matches normal t-shirt sizing. As of this writing, this is a good, cheap rash guard and many students have used it.

https://www.amazon.com/Elite-Sports-Compression-Training-XX-Large/dp/B07D1DRZT2

Spats: 

Optional but many prefer to wear these under their gi or for no-gi training (under their shorts). Most women consider spats to be "must-wear" apparel during no-gi training. As of this writing, these are good, cheap spats and many students use them.

https://www.amazon.com/Hawk-Sports-Compression-Running-Leggings/dp/B07NQMYJ29

Cup: 

Optional but many men prefer to wear these for groin protection. While one of the more expensive options on the market, the Diamond MMA is easily the most comfortable and most protective cup on the market.

https://www.amazon.com/Diamond-MMA-Strap-Jock-Large/dp/B00D2XGDUS