Skill Profiencies: Arcana, Nature (know a lot about monsters and animals)
Tool Proficiencies: Alchemist's Tools, Herbalism Kit
Gear: A one-handed, silver weapon, herbalism kit, pouch containing 10gp
Feature: Toss a Coin to Your Witcher
Witchers are known as monster hunters; in most places, they will be able to acquire work hunting some monster no one cares to deal with, and are often told rumors of the same. Their reputation as monster hunters can be a mixed blessing, but it may grant them access to others who would otherwise avoid strangers.
Toss in some alchemy rules so you can make "potions" and you're in a valley of plenty.
(Note: Because it was frequently asked: The witcher background only provides a silver weapon because your class usually provides a normal weapon, thus giving you the silver and steel weapons you need).