High End PC Not Functioning as it Should

[SinfulStreams]

So I have an MSI pc with an RTX 2060 SUPER, I7-9700, 16 GB DDR4 3000mhz ram, & 1 TB internal SSD/8TB external HDD. When I launch a game like the new CoD Cold War, one of threethings will happen: it works but the moment I join a lobby, it freezes and crashes, it'll freeze then I do ALT+TAB to another tab going back and then it works, or it just ends up working. Now there's an occasional plain freeze where everything just slowly gets kind of a breaking effect then after like 3-5 minutes of that, it'll give a "lost connection to blizzard app" error. Any ideas on why my pc is doing this? It's been going on for a little while now.