You have learned interval manipulation:
Merge intervals: : Sort by start, track last interval, merge when overlap.
Insert interval: : Three phases: before, merge, after.
Intersections: : Two-pointer on sorted lists.
Remove covered: : Sort by start (end desc), track max end.
Cover range: : Greedy extension, always pick furthest. Good job on finishing this section. Intervals are a favorite interview topic and you are ready.