Youtube is great resource for free tutorials on video editing. For a more in-depth, premium learning experience you could invest in a full course on platforms such as Udemy.
I have to knw what excactly your refering to. .is it the speech bubbles? Or both footages. From the video I can tell its two separate videos that are chopped and inserted in each segment separately.. you can use capcut or premierpro or aftereffects
You want to know how to edit video like this. First of all we should have to know that which editor is used to edit this video second we have to check filters and templates used in it. Then we can edit video like this. If you want to edit video on a professional level you should have to try...