You can convert hours and minutes into seconds in JavaScript using a simple formula:
seconds = (hours * 3600) + (minutes * 60);

Example Code:

function convertToSeconds(hours, minutes) {
return (hours * 3600) + (minutes * 60);
}

// Example usage
let hours = 2;
let minutes = 30;
let seconds = convertToSeconds(hours, minutes);
console.log(`Total seconds: ${seconds}`); // Output: Total seconds: 9000

Explanation:

1. Multiply the number of hours by `3600` (since 1 hour = 3600 seconds).
2. Multiply the number of minutes by `60` (since 1 minute = 60 seconds).
3. Add both values to get the total seconds.