Bearing replacement is super easy. You just lift out the old ones and drop in the new ones. No tools needed other than an Allen wrench. Nothing else needs replacing...most likely. Before you replace the bearings, however, you might try a clean and grease routine with adjustment of tightness. That could be all you need. Sometimes moisture will cause that creaking.

Assuming your steerer is not tapered (different diameter top and bottom) just Google: Cane Creek 40 Series, 41, 1 1/8" bearings. 41 mm is the nominal inside diameter of the head tube. Amazon is a good source for them. Easy peasey!

BTW, in future this kind of inquiry is better posted on the Bicycle Mechanics forum where the real experts reside.