your Pokemon can be up to level 100 then they are at max power
The highest level Pokemon you can catch is Lugia, which is level 70. You can find other high level Pokemon at Mt. Silver.
Victory Road has fairly high level Pokemon in it
High level Pokemon.
It's better to have a high Typhlosion level
You have to train him like a normal trainer with high level wild pokemon, trainers, and patience
Trading Pokemon for Starters, High level Pokemon for Low Level Starters Most Likely will work.
Numel evolves at level inyto camerupt which at high level is very useful at the Pokemon league.
with high friendship
No.
if your Pokemon are on a high enough level, every weekend you can battle you rival
No Pokemon is higher than Level 100, except in the TDG, where you can obtain level X Pokemon. It's also rumored that in the upcoming games, Pokemon Black and Pokemon White, that Pokemon can be trained as high as level 150.
I am pretty sure your Pokemon can learn it on a high level. :)