You are the Respondent if you have been served with a lawsuit by a Sheriff. Once you have been served, you have 20 days to file your answer at the Courthouse and you must count the weekends. If the 20th day ends on the weekend, then your answer must be filed the following Monday.
You may want to contact an attorney to discuss whether or not you want to file a counterpetition for dissolution of marriage. If you want to make sure the divorce goes through, then you should file a counterpetition. If there is no counterpetition filed, then the Petitioner may dismiss his or her petition for divorce at any time, and without a counterpetition on file, the whole divorce action will be dismissed and you will have to start all over again.
There is a filing fee for filing counterpetition unless you qualify for indigency status with the Clerk of Court. If you file a counterpetition, you will also have to prove your Florida residency. If your driver's license was NOT issued at least 6 months before filing your counterpetition for dissolution of marriage, then you will need to file an Affidavit of Corroborating Witness.
If children are involved, you do not have to file your own Uniform Child Custody Jurisdiction Enforcement Affidavit (UCCJEA) if the Petitioner has already filed a UCCJEA. If you dispute the Petitioner's UCCJEA, then you should file your own.