You are definitely one of the final candidates.
Nowadays, two rounds of on-site interview is very common.
But I feel that the next round will be the final round. Typically, there will be no more than three people in the final round; it could be only two.
Prepare the same way as you prepared for other interviews. In addition, do a lot of homework, find more information about the company.
When I interview people, I typically look for the information on three areas:
1. does the candidate have the technical capablities to do the job?
2. will the candidate be interested in doing the job
3. will the candidate culturally fit the company/team?
Good job. It is very likely that you will get the job.