Practice non-distraction. Start little.

Decide, for example, that you're going to make your bed. Then don't do anything but make your bed. Don't check your phone in the middle or go on a side quest to dust the headboard. Just make your bed.

Just keep practicing that on easy things and you'll get better. The key is to set tasks that you can achieve. As your brain gets used to this it will let you do more involved tasks undistracted.

Eventually you'll be able to non-self-distract for 30 minutes, at which point you can strategically use your time and make major accomplishments. That's about as long as anyone can work without some sort of break. If you can stack 10-15 good half hours in a day of work you're going to take over the world.