I will be happy to help you out, but the best place to learn about this site is from the forums on their own site. Just click the "Forums" on the top of the page.
The best way to view which planes you are traacking is by looking at radar view. You reach that by going to Premium - Radar view shortcut. You will need to enter your IP address then they show in red.
OR
You can go to filters, select your radar and it will show which planes are showing under your radar. Now, just because it doesn't show any airplanes doesn't mean it's not tracking. The stronger, faster radars seem to dominate the web page. If there are stronger and faster radar's then yours, then you would rather them show anyway. Remember, this site is for plane spotting so you want the best radar coverage possible.
Happy to help, but you will find all kinds of additional information on their forums page.