The time of running every day is not important. It is important to stick to it every day. When to run depends on your convenience, so it's easy to stick to it. There are some details. For example, the advantage of running in the morning is that you will be more energetic all day (provided you have enough sleep time), and running at night is good for your oxygen circulation and other details of your body. These two times are recommended by most people.

Do you want to run every day or every few days?

My suggestion is that you can run every other day at first and gradually increase the running frequency. The ideal state is that you don't feel tired or relaxed after running. Not less than three times a week, otherwise the exercise effect will not be achieved.

Is there any requirement for the length and distance of each run?

This still depends on your own situation, there is no fixed requirement. But the first thing is to improve step by step, not to improve too much at once, otherwise the body will be difficult to adapt, and the other is to persist.