Learn Swedish: Chefen stör mig inte, eftersom jag kan jobba var som helst. - The boss does not disturb me, because I can work anywhere.

In Swedish, you create "any-" words by taking a question word and adding the phrase som helst. Var means "where", so var som helst means "anywhere". Literally, helst means "preferably" or "rather", but as a fixed phrase it just creates this open, free-choice meaning. You can do the same with vem som helst (anyone) or vad som helst (anything).

Could I use vart som helst instead of var som helst here?

No, you must use var som helst here. Just like the rule for var (location) versus vart (destination/direction), you have to pick the right one for "anywhere". Because working (jobba) is something you do in a location rather than a movement toward a destination, you use var. If the sentence were "I can travel anywhere," you would use vart som helst.

Why is inte placed at the very end of the first clause?

In a standard main clause, the negation inte usually goes after the verb. However, when you have a short object pronoun like mig, dig, or den, the inte gets pushed after it. That's why it is Chefen stör mig inte rather than Chefen stör inte mig.

If I wanted to make the second half of the sentence negative, where would go?