@ggtpme,
Please go to brave://settings/system and you’ll likely want to set it to the last option so that tabs go inactive after a very short amount of time. Of note can you can add sites to this list that you’d like to “always” be active:
I recognize that this isn’t exactly what you’re describing but it is a start. There is a way to get what you want, however it isn’t ideal. You can visit brave://discards/ and manually deactivate tabs:
The downside here is that these settings do not persist across sessions. So when you close and reopen the browser, you’ll have to perform these actions again.