How can I put a video behind this text?

I want to delete the laptop image on the website and have a rectangular section with a video in the background as shown here: !Screenshot - c3f2a5becac30771a4c025e38a5d9e06 - Gyazo and the text and buttons on top of it.

How would I go about this?


Here is my site Read-Only: [LINK]1
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