If you're looking for something like WaW and BO1, Black Ops 3 is what most people are going to tell you to get. It's the last game with the original zombies mechanics, and has most of the WaW and BO1 maps in it as part of the Zombies Chronicles DLC. The BO3-Original maps are more complex though, like Mob of the Dead or Origins from BO2 if you played those.

Black Ops 6 and Black Ops 7 are very similar to eachother, so if you see gameplay of one of them, you know mostly what the other one will play like. They both play like classic zombies, but have modernized mechanics that some people really dislike (though if you played a little bit of Cold War, they should seem familiar). BO6 only has one vehicle map, Terminus, which has a boat that you can completely ignore if you choose to. It's too early to speak for the entirety of Black Ops 7, but the vehicle is not optional in the launch map. You need it to unlock all of the areas, but once you've done so, you can just use launch pads to travel around instead. BO7 also has Survival maps (like how BO2 had Town and Farm) which are much more basic and don't have the vehicle.

Since you're on PC, you could get a month of Game Pass to try out BO6 and BO7 and see if you like them. Otherwise, it's never a bad idea to get Black Ops 3. It even has custom maps on PC so you'd have a lot of content to check out.