Samsung Health does not sync natively with Google Fit. However, there are several third party apps that can help you sync your data from Samsung Health to Google Fit. Please bear in mind that we are not affiliated and don't specifically endorse any of these apps.
Here are the steps to follow:
Setup Samsung Health on your Android mobile device
Link Samsung Health to Google Fit using a third-party app such as:
Health Sync (paid)
Health Connect (free beta)
Link Google Fit to the FitBark app (guide)