You can reset the progress by selecting specific user roles and specific courses and also if you want to reset all the courses’ progress together.
Steps:
1- You will find the Reset by user option in your WordPress admin area navigating to the LearnDash LMS menu ➡ Reset Course Progress ➡ Reset by User Roles tab.

2- Select the User Roles you would like to reset the progress for.

3- Select the Reset Type, either you have to reset course or quiz progress.

4- Select courses/quizzes that you would like to reset for the selected user roles.

5- Press Reset.

That’s it! ?
You just have reset the progress for the selected options.