For use Call to Glory with the additional cost of the buff, do I need to have the runes of cost ready or not?

No — if you pay the buff cost, you don't need any runes.

Call to Glory's additional cost is "spend a buff; if you do, ignore this spell's cost" — so its 3 Energy cost is set to zero and you pay nothing else. The buff and the base cost are calculated and paid together: either 3 Energy, or 1 buff from a unit you control (Rule 356.1.b.2; FAQ #6740). Your runes can be fully exhausted.