The USA does, of course, define a “grace period” in its patent law. This is a period of one year prior to the filing date of an application, during which the applicant’s own disclosures do not count against the validity of a patent granted on the application.
Many US inventors greatly appreciate this rule. It gives them the opportunity to try out their invention in the market before having to incur the costs of seeking patent protection. However, I strongly recommend that they do not do so.
The reason is simple; almost everywhere else has a requirement of strict novelty, or (in other words) no grace period. So the moment you disclosed your invention in the USA, your right to patent the invention almost everywhere else just died.
Fortunately, there is an alternative. File a “provisional” patent application instead.