Yes. When you go to vote, a poll worker will verify with the auditor’s office that your absentee ballot has not been returned. If it is confirmed that the auditor’s office has not received a ballot from you then you will be given a new ballot to vote there.

It depends on the election. In primary elections, you can only vote for candidates from the party to which you belong. In general elections, you are free to vote for anyone you like, regardless of their party affiliation.