How to add one hour to current time

JavaScript
1

Hi

I want to add one hour time to current time. Please help me out

suppose if user enter the pickup time as 11:00 clock and the system time is 11:15 then I want to display the pop up message
that please enter the time more than 1 hour from system time.

Please help me out

Thanks & regards
MD.Samiuddin

2