Difference between "been to" and "been in"

Solution 1:

Been to indicates that you are talking about trips or journeys specifically to Florida. To is a preposition of motion and you are talking about movement towards, and arrival in, Florida.

Been in connotes a stay in Florida (which may be short, or very long, or simply passing through). In denotes position, and you are talking about the state or condition of being located in Florida. It doesn't matter whether you took a trip there or not.

Solution 2:

• "He has gone to Paris" means he's there or on his way (to Paris).
• "He has been to Paris" means he's visited Paris (but he's back now).
• "He has been in Paris for two months" means he's in Paris now (and has been for the past two months).