That's very nice old Navy style Anchor !
I was a Shipwreck diver for many years and we recovered a lot of old steel Anchors.
First use a Wire Wheel to remove any loose material.
Then to prevent future deterioration - soak the Anchor in a Lye Bath for 4 to 6 months.
Wash with Fresh Water - Brush on a heavy coat of Primer and then a few coats of Black paint.