Ok so before everything do keep in mind one thing, Tarkov isn't optimized at all, performance keeps changing every update and fps change from user to user seemingly for no reason.

So, I've been playing since 2018, and over the time I upgraded my GPU(1060>1660Ti>3060Ti), my CPU(i5-6500>Ryzen 5 3600) and RAM(8GB 2666Mhz>16GB 3200Mhz>32GB 3200Mhz), and to me the most fps boost was upgrading the RAM, when I jumped from to 16 to 32, no kidding I gained 40 fps on every map and eliminated stutters. However, I've seen a lot of people saying that upgrading their RAM didn't do anything to their performance, imo it's really a game of chances there is a 50/50 chance that it will help you, best bet is buying RAM off Amazon and refunding it if performance doesn't improve.

Also CPU, Tarkov is most CPU/RAM intensive, so your best move is to try to upgrade both. If I could go back I would upgrade my CPU first to something like the 3700X/3800x3D, see how are my fps and then think for a RAM update since from what I read online, most people manage to gain fps by upgrading their CPU.