While substantive office actions are generally harder to overcome than non-substantive ones, keep in mind that office actions are a natural part of the trademark registration process, and many applications receive one.
First, it's important to understand the contents of the office action to estimate your chances of success. In the office action, the examiner will describe the issues and offer steps you can take to remedy them. These might include amending your application, providing proof that your mark meets the examiner's criteria already, reaching out to third parties to negotiate consent, etc.
If you are not sure how to read the office action or how to achieve the resolution proposed by the examiner, it's highly recommended to talk to an experienced trademark attorney.