"form" refers to the way you run; e.g., arms bent, back straight, etc."When setting yourself a reasonable goal for your first run, don't worry about speed or form: time is of the essence. You should simply aim to jog for as many minutes as you feel comfortable and 'within yourself'."
"aim to jog for as many minutes as you feel .... within yourself" refers to how much energy you have within yourself to continue jogging.
Student or Learner