You want the best CFA score possible. An outdoor track with long straight sections will yield your fastest time. That's why all world records are set on outdoor tracks. The problem is that, as you know, the run is timed at the end of the (usually) indoor portion of the test with only XX amount of time allowed between each event. You should find a gym with an outdoor track just outside in order to maximize your score. This is usually a HS, but I assume that yours is not that way, so is there a college, YMCA, or something similar nearby? Also as I remember, the CFA results can be submitted as late as January (please be guided by the handbook, I am going on memory.) That means there is plenty of time to practice that BB throw, pull-ups, etc. Unless you are at max level for all stations of the CFA, I recommend you continue to work out. See where you are in August/Sept. before asking your gym teacher to test you. There are numerous threads on this forum for advise on CFA. Good Luck!
