This is new material. Remember the arc intercepted by an inscribed angle is twice the measure of the angle, or the inscribed angle is one-half of the intercepted arc. There are 360 degrees in a circle and 180 degrees in a semi-circle.
Here are some online references if you need them.
https://www.varsitytutors.com/hotmath/hotmath_help/topics/inscribed-angles
https://www.dummies.com/education/math/geometry/inscribed-angles-and-arcs-practice-geometry-questions/
the videos below are part 1 and part 2
https://www.youtube.com/watch?v=AYrTQivQHZI
https://www.youtube.com/watch?v=fZZmmdMpU7o
From the worksheet do problems #1-18.