How to know if my MacBook Pro is refurbished or not?

Like stedman1, I am curious why your think your compure is a refur.

I know of no way to tell with such a new Mac. Prior to about 2009-10, Apple prefixed serial numbers on official refurb models with "R" or "RM." They've not done that in a long time.

Apple only sells refurbs web-direct, and those come with a full one-year warranty and are eligible for AppleCare+.

Some resellers claim to sell refurbed computers but most simply wipe the outside. Some do not even bother to properly reset the computer soe a new use can log in.

You can enter the serial number here and see what that shows for support/warranty coveage:

Check Your Service and Support Coverage - Apple Support

Any Apple product sold as a "refurb" by other than Apple directly through their online store may be called "refurbished" but you have no idea of how thorough that was.

Unless you bought it from Apple's Certified Refurbished product page, then it was not refurbished. It was used.

Its original purchaser may have bought it from that page, but that would also make it used.

Where was it purchased?

Did you actually purchase a refurbished unit?

Why do you suspect it is refurbished?