Getting better at Cross country Mt. Biking?

[FudgemsBox]

I just joined my schools MTB team. We had our first practice today, and i was the slowest. I have never done cross country mtb before.
Also the bike i have is alright, not suspension in the front.

the biggest problem i had was going up hill. it was a a 5 min climb, but i was so slow and behind, i even had to walk the bike up a little bit.

Is the best way to practice going up hill, by just practicing going up hill non stop?
or is there some other ways too.
I want to stick with this, and i want to keep up with those on my team.

also, going down hill, i was way behind everyone. since i do not have suspension in the front, it was real REAL! bumpy. Also, i didn't feel so much control going down. so i went slower than the rest.

any tips for going down fast?

should i just bomb it? or is there a good technique?

i do not have any suspension, any tips for Cross country racing without suspension?


also, when i ride on the road, my MTB feels real sLOW!.
i no its the rider as well, but on my dads bike, i feel like a i go faster on his.

on my MTB it seems like the tire is a little out of air.
any tips?

Thanks