How to give alert on click button when Minimum checkbox is not checked in JavaScript?

Name: Redmi Y2 Tech Review
Uploaded: 2018-08-05 T20:00:00+05:30
Duration: 6 min 59 s
Description: Namasty dosto is video maine Xiaom Redmi Y2 bare mein baat krunga, or sath hi Redmi Y2 ke kuch key features aapke sath share krunga. 1. Dual 12MP + 5MP cameras width Precise bokeh effect. 2. 16MP front camera width 4500K soft-toned light.

Javascript checkbox checked