If i have my tonsils out, how will my voice change?

No change: Many great singers have had tonsil removal and their voices do not change. Remember, the voice is produced by traceho-bonchial air moving past the laryngeal opening. The removal of the palatine tonsils, if anything, could improve the quality of the voice by expanding the supra-laryngeal space (space above the larynx). This space changes the quality of the sound produced and may improve it.