I believe connecting with your school's foreign study office is best to see what programs are sanctioned and most importantly what programs will provide academic credit for your study. There are many for profit programs including Education First which may also be approved and sanctioned. You also want to see if you can get scholarships or aid for any of your programs.
Education First is a great program to ensure a fun and safe visit. I personally attended API Florence, Italy and found it completely organized. I got free excursions, free safety lessons, new friends, and phone numbers to call in the middle of the night if I was in trouble. 10/10 would go again.
I think it is wonderful that you have decided to pursue study abroad. As the answer above points out, your college might have an office or counselor that would provide advice on study abroad programs. Make sure you choose when where you would get full credit for the classes you take. If you are looking for a specific provider of study abroad programs, try the School of International Training (SIT).
They are based in Vermont but they offer very interesting programs all over the world. I attended their programs in Brazil and Switzerland and had a wonderful time. Good luck!