Using If Statement in VBA Code

I have decided to attach my excel spreadsheet so that you can understand what I am trying to accomplish. Again, not sure if it is even possible, but worth a try. I did try adding the code that you recomended into the visual basic editor, but not sure if I did it right, as it does not seem to work. All of my other applications that have code attached to them also have a button attached to them, but in this case, there is obviously no button. So is that all I do, put the code into the visual basic editor?

Again, what I am trying to accomplish is this: If the mechanics available hours in column B is zero, then I don't want the user to be able to enter numbers into the corresponding column in the appointment part of the spreadsheet. So if B4=0, then lock cells E14-E47.
The password to unlock the spreadsheet is "service".

Thank you so much for taking the time to try and help me.

I'm sorry, but what is a change event? Again, I am a novice at this VBA stuff, so I'm not sure how to use a change event to trigger the macro. Still not sure if the code works, because again, I don't know how to trigger it. Hopefully you can help me put in a change event.

Thanks so much

Wow, it finally works. Thank you so much for your assistance. I truly could not have accomplished this without your help. One last request. Is it possible to also have the locked cell make a chime noise at the user, if they try to enter data into it when it is locked? If possible, how would you add this into the previous code that you sent me?

Now that the code that you suggested works for this technician, I went to copy it over for the other technicians so that for example if Cell B5=0, then now cells F14-F47 are locked and so on and so forth for all of the technicians. But I keep getting this Compile error, that says Ambiguous name detected: Worksheet_change. Can't I use the Worksheet_change command for all the technicians?

The locked cells are kind of working, but there must be a little glitch. If I give the technician say 6 available hours, it will let me assign time under their name in the appointment part of the worksheet, but if I put my cursor in the cell where I had assigned their time, and then use the delete button on my keyboard, then it will no longer let me re-enter a number in that cell. It is now locked. The only time those cells should be locked, is if their corresponding available hours is zero.

Also the beep is not working, but that doesn't really matter to me. It really is not important. Let's just get the other working. I should know better than to try and accomplish too many tasks at once

Thanks again

even in your example, if I set Tony's available hours to 7, then I go into Cell E14 and type 2. Then maybe I decide that is wrong, now I click in cell E14, and click delete on my keyboard. Now I want to re-enter 1 in Cell E14, B4 is still 7, but for some reason now the cell is locked and won't let you enter data.
Hope this makes sense

Thank you so much for all of your help. The sheet seems to be working as planned, and I really could not have did it without your help.
Could you please mark this thread as SOLVED.