Hi and welcome, please check out the Newbie Guide if you haven't already:
https://wiki.project1999.com/Newbie_Guide
Are you considering the mobs before attacking them? From memory things like polar bear cubs can be level 4 so will whup your butt if you're level 1. Decaying skeletons are normally the easiest mobs to kill and have the added bonus of sometimes dropping weapons and cloth armour which help you buy your spells. Even decaying skellies can be tough at first though until you get some skill-ups.