Time is a difficult concept to grasp, frame, and master. But, as humans, we try mightily to do so.
The simplest time concept, I think, is the continuum—it’s all the same thing, going on and on.
Then you can get fancy, and introduce starting and ending points. Events, you might say.
Sometimes you can employ/deploy the idea of hinge points, or pivots, when something happens and things change going forward.
I keep thinking that overall it’s a matter of perspective, that reality is subjective, that we’re just fleas on Mother Earth’s back, belly, or neck.