How can these parts be removed
With a punch from where the outer bearing used to be
Carefully punch on alternating sides to hopefully save the seal cup if it's marked so you want to reuse it.
If it's a Tapered roller bearing you can knock both out together using a wood block from the other side. Your local bearing supply or auto supply should replacement parts for the inner side, not so for the outer bearing .
Many times there is not enough lip of the bearing cup showing for the punch to contact for a good hard hit. I run a bead of weld around the face of the cup where the bearing runs and let it cool. The cup will shrink enough to easily come out with some light taps.