I`m at Tel FYR and i don`t have levitation potion. Don`t know how but i don`t have it. I there any cheat or something or does anybody knows where i can buy it.

Meh, its easier to just buy a levitation spell and cast that. Check at the mages guilds...

I have bought it but i fail to cast it. I`m nord.

thats cuz ur alteration skill and probly willpower are too low. you can tell by looking at the spell in ur menus to the right of the spells, or when playing look at the magic symbol at the bottom (the one to the right of your hp and weapon symbol) then theres a bar at the bottom and that also show the spell chance
and i dont think being nord has much to do with it

it does since they don't get bonuses unlike Bretons and High Elves (advised races for magic type characters)

also I'm going to guess his level ain't that high which means his INT and Willpoer will be low

make a spell with 2pt duration and 1pt magnitiude on target, now keep casting that spell (if you wish to work better with levitation then use a spell effect governed with alteration)

after awhile alteration will level up, after 10 levels you will gain a character, if you had trained alteration and nothing else up you will gain a x5pt gain for the governing attribute which is either willpower or intelligence

both are important

on the other hand, to get up the tunnel you don't need a massive spell, just make a spell like: levitate 1pt for 30 secs (if still not able to cast make it less time)

once able to cast just go straight up and land on any side, from there you can jump to which ever side you need to be on

Man ur god!!!

An alternate solution is to use Chameleon from ammy of Shadows and pick the lock in Vivec Fighter's Guild where Sjoring Hard Heart is to get Dwemer boots of flying. I think they are Levitate 20 point for 10 sec on self.

wait! i have a solution to ur problem, i cant remember how to get it (so look in the FLD) but its called the "travel stained pants" they levitate when casted. it uses no magicka, just charge and charge wil RE-charge.

you get them after you do the corprus part of the main quest

they are one of the "gifts" from the past incarnates in the cavern of incarnate, so they are useless for levitating in Tel Fyr since you can't get them until after you cure the corprus disease

if my memory serves me i think there is a levitate potion in tel fyr. but like i said its been a while and its late so ill look into it.
(that time in the corner is wrong i havent bothered to change it)