Thank you for posting your question on History Hub!
A search in the National Archives Catalog unfortunately did not render any results for population/immigration migration patterns to Florida in the early 20th century.
I would recommend that you reach out to either the Florida State Library and Archives or the Florida Historical Society as they might be able to provide you with more information on the topics that you’re requesting. Links to both agencies with their contact information can be found here:
We hope this information is helpful and best of luck with your research!