Do i need to get the old wheel bearing pressed out and the new one pressed in the steering knuckle. Or is there a way i can do it at home my self? Thanks

you can tap the bearings out yourself using a punch and hammer. You can also tap the new ones in, very carefully, hitting only on the outer race, and being careful not to scrape the bearing face on the knuckle. It's good as well if you use a brass punch instead of a steel one. Just slowly work your way around the bearing, and take your time using light taps with the hammer.