PLEASE HELP 10 POINTS TO BEST ANSWER ON SKATEBOARDING?

I have been skateboarding for 2 years. Just two months on a good, non plastic truck skateboard. My friends are so good already (skating for same time on good skateboard, and they never used one with plastic trucks) They can ollie, almost kickflip, go down ramps, pop shuvit, almost heelflip, kickturn, axl stall, rocks fakie, rock and roller, and some other variants of those. I can do a switch like them, almost boneless, lazy fingerflip, occasionally kickturn, and I'm getting close to three second manuals. Also I can't even go down ramps. Why do I suck?