Click on Add/Copy Role
Here you can give a name to the role, described. When creating a new role, you need to chose the type of role and also if you want copy permissions from the existing roles.
Once your role is created you can go to permissions and filter your newly created role.
Now if you select on each permissions, you can see the option to add or remove your new role from that permission.
OWNER, ADMIN and VIEWER are default roles which you cannot change. But other user-defined roles can be removed or added to the permission.