Procedural programming is classic programming where the program language is used to tell the computer EXACTLY what do do - step by step. Examples are Assembler, Fortran, Cobol, C, etc etc. Very detailed, very difficult and time consuming to write, but very efficient from the computers point of view.
NON-procedural programming is where you tell the computer what you want, and it figures out how to get it. Non/P programming is often used for database manipulations, like SQL, Visual Basic, etc etc.
A SQL command like "Select name, address, city, state, zip order by zip" is non procedural. That one line replaces dozens, or hundred of lines, that would be needed to do the same thing in Cobol or C to get data out of a database.