Centrifugal Force

I don't know the answer, but a physicist recently told me that centrifugal force is fictitious. That person also said "No matter what one does in outer space, the centre-of-mass will not move, and that is true even of the rocket". I disagree with that comment.

The newton (symbol: N) is the unit of force in the International System of Units (SI). Expressed in terms of SI base units, it is 1 kg⋅m/s2, the force that accelerates a mass of one kilogram at one metre per second squared.

https://en.wikipedia.org/wiki/Centrifugal_force

Give no energy to massive circular reasoning that "centrifugal force" was used to inscribe the edge of British £2 coins with "standing on the shoulders of giants".