This is a feature only admins of the practice have access to.
Step 1: Go to your Practice Settings and under Practice Members:
Step 2: Click the Eye to Disable Provider:
Step 3: Confirm you want to Disable Provider:
Note: If you ever need to undo this, you can do so by going back to Practice Settings, scroll to Practice Members, and click “View Disabled Providers”
Related questions: How to hide a provider? How to transfer clients? How to remove a provider from my group practice?