A typo on a resume is very bad. Hiring managers view such mistakes as careless, and carelessness is an unattractive quality in job candidates.
Still, a typo in your resume is no reason to lose hope. Hiring managers review hundreds of resumes every day, so they read quickly. They might not even notice your mistake.
If your typo is easy to spot, sending an updated resume and explaining that you sent the wrong version before could help. However, sending the wrong version also signals carelessness. The results depend completely on the hiring manager’s judgment.
In the future, triple-check your resume for typos, and ask others to proofread it as well.