Drop Down selection requires another field to be completed

Hello,

My JavaScript knowledge is almost 0.  I have a form where when the user selects the Meal Type from the drop down, 3 fields will require data input (Meal Service Time; Number of Daily Servings; and Availability Time) and another field (Availability Method) will require a drop down selected.  Historically, I have had issues with my users not entering all of the information.

Based on the research I did on similiar subjects in the support community, I think this might be best done as a validate.  But I have no clue on how to even start that.  I think that on the Meal Type field which will trigger the required fields, I should assign an export value for each drop down option.  There are only 2 options.  Do I make the option True or 1?  And then how to I write the validation script for the other fields to require them. Any help is greatly appreciated.