As seen in the explainer, here are useful tips for working with keyframes:
To jump from one keyframe to the next, use the ‘go to next keyframe’ and ‘go to previous keyframe’ arrow buttons on the far left of the current layer property:

To ‘snap’ to a nearby keyframe when scrubbing across the timeline, hold down the SHIFT key on your keyboard as you scrub:

Everything you could ever need to know about keyframes! (click to view)