What are each of the different branch protection settings?

Enable Branch Protection

Choose one of the below options for the branch you are protecting:

Disable Push - No users will be allowed to push to this branch. This setting is often used when you want all users to create branches when making changes to the code.
Enable Push - Anyone with write access will be allowed to push to this branch. This setting is helpful if all users should have the ability to commit and push directly on the branch.
Whitelist Restricted Push - Only whitelisted users or teams will be allowed to push to this branch. This setting is often used when you want specific users, like managers or senior engineers, to have the ability to commit and push directly to the branch while other users need to create a branch to make changes.

For the Disable Push and Whitelisted Restricted Push settings, users will still able to commit locally, but the push will fail with an error. Communicate this setting with your team, so that they don't run into the error on push and need to revert or remove the commit from their local repository.

Enable Merge Whitelist

Only whitelisted users or teams are allowed to merge pull requests into this branch. This setting is useful if only certain users, like managers or senior engineers, should have the ability to merge pull requests.

Required Approvals

This will block the ability to merge pull requests until the number of approvals has been met. However, Administrators will still have the ability to merge their pull requests. This setting is great for when there are write users that need to have their changes reviewed before being merged.

Restrict approval to whitelisted users or teams - This specifies which users or teams are allowed to give approvals to count toward the required approvals. Without approval whitelist, reviews from anyone with write access count toward the required approvals. This is helpful if there are specific users, like managers or senior engineers, that need to review changes before they can be merged.

Additional Settings

Block merge on rejected reviews - Merging will not be possible when changes are requested by official reviewers, even if there are enough approvals. If one of the requested reviewers selects Request Changes on their review, then the pull request will be blocked from merging.
Block merge on official review requests - Merging will not be possible when it has official review requests, even if there are enough approvals. All assigned Reviewers will need to complete their review before the pull request can be merged.
Dismiss stale approvals - When new commits that change the content of the pull request are pushed to the branch, old approvals will be dismissed. The new changes to the branch will need to be reviewed and approved before they can be merged.
Block merge if pull request is outdated - Merging will not be possible when head branch is behind base branch. In this situation, the pull request will prompt you to Update Branch.

Protected File Patterns

This is a way to set up protected files that are not allowed to be changed directly even if user has rights to add, edit, or delete files in this branch. Multiple patterns can be separated using semicolon (';'). This setting is helpful if there is a specific file or file type that you do not want users editing or adding to the branch.

Examples: *.yml, /docs/**/*.txt.

Please note that users will still be able to commit these file changes and file types locally, but the push will fail. Communicate this setting with your team, so that they don't run into the error on push and need to revert or remove the commit from their local repository.