Well, looking at the screenshots, it seems like normal usage to me, GPU will always consume that much memory to function when you watch videos and all that but the other services seem okay.
The other one that will always use is the main Browser process and 399MB is okay.
One thing, in my opinion, you should remove DuckDuckGo extension, it uses more memory than most processes, and it is useless because Brave already will do more than it, there is no real benefit about it and it will run on every page which means it might affect something. But it consumes ‘a lot’ of memory for what it will do anyway even a 0.1 CPU usage.
But usage seems okay, you should check when you see 2GB memory usage and see if it is like an extension or just a website being heavier than the usual.
But Chromium has many protections like sandboxing and isolation, which are useful but also made browsers create more processes and use more resources, especially to protect against spectre, so that’s why so many processes for subframes and dedicated/service workers and all that.