I am installing a new HDD can I run the newest issue on it?

If this is the latest MBP then yes of course you can install the latest macOS Catalina

Apple MacBook Pro A1278 Price (19 Oct 2019) Specification ...

The MacBook A1278 line of laptops used to have two divisions -- a MacBook model and a MacBook Pro model. Apple released the last version of the basic MacBook model in 2009.

As you can see the model # does not say much for your exact Mac.

macOS Catalina - Technical Specifications - Apple Support

macOS Catalina - Apple

Changing the hard drive won’t change the upgrade requirements.

Which Mac do you have?

Which version of OS X?