Your biggest problem will be getting the freewheel off the rear, theres a few methods to do this but the easiest that won't damage the hub,
1) lace the hub back to a rim using the non drive side and hold the rim
2) put old spokes throught the holes on the non drive side, make loops at the end of the spokes and put a screw through each loop and fasten to a piece of ply.
3 this way
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Bearings are fooked, swap out the bearings, it's no biggie for a of your man of your capabitlities.
Hold the alloy cover with the dedicated spanner and take off the cone lock nuts, when you've undone one side the axle will slide out, the alloy covers slide on and off the cones.
To get the old bearings out you need to make a tool but that's easy enough I'll put a pic up of one I made tomorrow or monday.
You'll find the number of the bearing you need on the rubber of the bearing.
Your biggest problem will be getting the freewheel off the rear