I do not believe it is necessary to crate or confine a dog when you need to do your thing, like work or take care of your needs -- unless it is a safety issue for your dog.
I trained my 2 Yorkies by establishing a daily routine. They are with me almost 24 hours a day, and they know when to expect meals, outings, and so on. They also know when I need to work or do my things.
We have brief play sessions or together time during the day, but then I say, "Time to work." Although I have 2, they do not self-entertain.
I take them to a park to walk after dinner and that usually tires them out for the rest of the evening. They also come along with me on car errands during the day because they love car rides. The rest of the time, they usually chill in their beds or watch things out the windows.
Having a daily routine helps establish expectations and has a calming effect.