You can open this page by clicking the Side Menu->Admin->Skill Levels.

This page shows the level groups that you can optionally associate with skills and qualifications. Level groups represent levels of attainment or experience in the particular skills the candidates are associated with.
For example, you can create a level group called experience with levels of Beginner, Intermediate and Advanced. Then you can associate the experience level group with any appropriate skill so that when you use it in candidate or vacancy record, you will have a drop down box with Beginner, Intermediate and Advanced as separate options.
You can use to assign any set of values with a hierarchy from low to high, with up to 20 values available per level group.
You can add a new level group by clicking New Level Group.
To edit, click a level in the list.
You can add or edit the title of the level group and also assign the different weightage for the levels.
WARNING: If you have Beginner and Advanced as levels, put Beginner in slot 1 and Advanced in slot 20. That way any number of intermediate levels can be added later without moving the existing values. Please do not change the meaning of or remove a level item once it is in mature use as it could mean orphaned values or general system confusion.