While there are some stories that move along at a breakneck speed, without any gaps in time or breaks (The Hunger Games being a good example), this is not true of most stories.
This is why it’s important to learn how to transition between the different points in your story while “filling in the blanks” about what happened between point A and point B.
That’s not to say that you want to completely summarize the events that occurred in that space of time (though that is a possibility). What usually works best is to reveal small tidbits here and there - that’s just enough to bring a dose of reality to your story without bogging them down with details.
For example, in Harry Potter you get this a lot as the characters take a minute here or there to talk about their homework or think about things that have happened since the last chapter. Most chapters actually take place weeks apart, until you get to the later books where things are packed in a little tighter.
The point in all this being, unless it’s a very action-oriented plot (as is the case with THG), it actually breaks the suspension of disbelief a bit to have one thing happening right on top of another, and etc., etc. Building in these breaks and transitions, and then throwing in a few little details to remind your readers that the characters were still going about their ordinary lives when the reader wasn’t looking, help to bring your story to life.
This tip is from legit-writing-tips on Tumblr