You can only tell an enemy's level by looking up their name on a site which catalogues such things. All enemies with one name will be the same level and have the same stats as ones with the same name. When you level up high enough, enemies of a higher rank may start to appear, and some higher level ones are fixed and always appear in certain places.

For example, take Draugr. If the enemy is just called 'Draugr', then it is Lv1, if it is 'Restless Draugr', then it is Lv6.

Lv13 = Draugr Wight,

Lv21 = Draugr Scourge,

Lv30 = Draugr Deathlord.

Then for Bandits,

Lv1 = Bandit,

Lv5 = Bandit Outlaw,

Lv9 = Bandit Thug,

Lv14 = Bandit Highwayman,

Lv19 = Bandit Plunderer,

Lv25 = Bandit Marauder.

Some Draugr carry them usually. Otherwise, at the temple in Riften, the priest there has one for sale.

it has alot of life. i choose to run and fight

You can buy one from the priest in the temple in Riften. Other than that, you can find them in dungeons or chests on your journeys. Some draugr will carry them as well.

The symbols are behind each pillar, if you look closely, just above each one, hope I helped. I also got stuck on this one, behind the door is more draugr :)