I also have ADHD, and notifications and disruptions can easily distract me from my focus. When I work from home, I use an old-fashioned kitchen timer. I set it for a specific period and concentrate solely on the task I want to accomplish. Initially, you may only be able to focus for 5 minutes or so, but over time, you may be able to gradually extend the duration. For me, it’s crucial to turn off notifications on my work computer during my focus time. When I take a break, I check if I missed anything, look outside for a while, or go for a quick walk before returning to work.