Find the end date & time considering work hours

[ralphp312]

I need a formula where I have a determined start time + planned dd:hh:mm equals the end time with consideration of 1) work hours, 2) holidays & weekends excluded.

Example:
Work Hours = 5:45 AM to 10:00 PM (M-F)
Start Date/Time = 4/8/20 9:37 AM
Planned Time = 1:14:28 (formatted as: dd:hh:mm)
End Date/Time = 4/10/20 2:58 PM (how to get this result)