So the only time ive done the college of winterhold was at level 15 and the final battle was almost impossible for me. So if i went in at level 10 or lower would i get blown to pieces or would magnus be set to my level?

I did the entire College questline starting from level 1 and did nothing else except for the main college story arc. I was level 14 when I became archmage.
You can do it.
-Loth

PS Get the lightning bolt spell as soon as you can perk Apprentice Destruction... it helps. Don't forget that you can use scrolls, too. If you find any bane of the undead scrolls, hang on to them and use when appropriate.

I found myself unable to kill the Draugr Deathlord in the Under Saathal quest. A check of the mob on the wiki reveals he's level 30 whilst I'm only level 18. It appears that that particular mob scales to level.

the lower the level the easier the quest will be. Summon a familiar when needed to take the aggro off you. The guy who helps you out will probably be quite a bit more powerful then you are at level one. I did the first quest at level 46 and pretty sure they were deathlords or something like that. Nothing 2 dremora can't handle. I don't know if it's doable on master difficulty at level 1 however. Probably not.

A low level conjurer mage with 100 conjuration could do it easily, along with many/most quests for that matter if they keep themselves stealthy. The dremora pretty sure are a fixed level in the upper 40's, so at a low level they will destroy everything on any difficulty level.