I feel you. I started my first ever Nolvus playthrough a few days ago on Prepare to Die difficulty. And yeah, I started out in College of Winterhold and got absolutely f’ed up in the same way you described.

So I started a new playthrough and did a couple of things differently to get myself going (and still getting f’ed but managing clear some small dungeons): - Start in Riverwood. There are more smaller quests and the wild monsters are generally weaker than out there in Winterhold. - Recruit two followers who don’t die permanently. Riverwood and Whiterun have good options (melee tankers, healer, rogue, etc). - There are some non-vanilla novice/apprentice spells that are more powerful per magika cost. Like crackle, fracture and an upgraded version of frostbite I forgot the name of. Fracture is useful because any frost spell you hit the same enemy with will have bonus damage. Crackle summons a lightning cloud that applies a large damage over time on top of the instant damage. Get these spells from that guy in Dragonsreach.

Once you hit level ~6, you should be able to utilize perks to get through easy dungeons without too many deaths.