Fetch and get are both transitive verbs. They require an object noun phrase.
- He fetched the butter from the pantry.
- She got a letter from her brother today.
Without the object, they're ungrammatical.
- *He fetched from the pantry.
- *She got today.
They don't mean the same thing, either. Fetch has a very specific meaning:
- go somewhere else, pick up something, and return with it
Get, on the other hand, has many different meanings, though only the one meaning 'come to have' (or 'cause to have') is involved here.
The OQ doesn't provide sufficient context for an answer -- just for starts, what is to be fetched or gotten, for what purpose, from where, and by what means? -- but I would suggest that a complete sentence is more informative than a verb phrase with an imaginary object. It is never wise to believe that your readers have exactly the same imagination you do.
And I wouldn't recommend either fetch or get, either. One is rare and dialectal, the other is overly common and multiply ambiguous; and they're both ungrammatical without objects.