How to create needed macro for timesheet

Question

I need to write a macro to log entries for a respective pay period based on entries keyed by the user for that period. A user will key in hours worked into C19-34. They will then click the command button 1 "Post Hours". The script will take the total hours in C35 and enter the value next to the respective pay period in column G. Users will only be able to key entries in the green highlighted area. The sheet will be locked for everything else. No idea how to write this script.