What is the difference between "start" and "start on"?
The difference between "start" and "start on" here is that "start on" is a phrasal verb used to mean to start working on a task or activity. Ex: If you start on one project at a time, it will be easier to get everything done. Ex: Get started on your homework. In comparison to this, "start" is just the basic form of the word. So you can always replace "start on" with "start", however, it will not have the same nuance of beginning to work on something.