What are usually metal that combined near protein to form it function?
Hemoglobin contains iron.
Not sure if I figure out you question, but the protein which carries oxygen contained by your blood (haemoglobin) is a protein formed around an Iron atom.
Sorry if I'm stating the obvious here, iron is a metal which in its solid elemental form is usually found as "iron ore" which is where on earth we get iron for our industrial uses. I'm guessing that's what you meant, yeah?
There are many different metal ions which act as cofactors for protein function. Haemoglobin is one example, as mentioned by other posters (though the iron ion is technically bound by a porphyrin ring, which next binds the haemoglobin protein). Another example is calcium: many different proteins can bind Ca2+ ions, changing their function. Zinc, copper, and masses other metal ions are also used by the body in this way.