Do only what you can do, the rest leave to someone else or just don't attempt it.
You cannot do it all. You cannot actually multi-task. Ego stands in the way telling you that "you can."
Beyonce doesn't pack her equipment when she goes on tour. Taylor Swift doesn't fuel up her own jet or tour bus. Tiger Woods has a caddy to carry his golf clubs. Lebron James doesn't meal prep his own meals. Steve Jobs and President Obama wore the same thing each day.
The point here is performers, leaders, athletes focus only on their craft, art or job. The rest is automated or left to someone else to do. Perform or plan to perform; this is all they do.
You might not have the resources to delegate things to others. Than skip that step. But you can do less of what you aren't good at or less of what you don't care for. By doing more of what you love or are good at, results will change. Then comes the added benefit of the satisfaction you get. And the peace of mind that your focus or what I call concentration, is benefiting you and your life.
As a writer I only write or prepare to write. I am not busy learning about Bitcoin or how to create an abstract painting.
By doing less you get the benefit of doing better at what you decide to focus on. By doing more of only what you can do, your progress magnifies.