I signed up to do a Journalism/Social Media and Marketing internship with Adelante Abroad. Unfortunately, I wasn't placed with a magazine which would have been preferable, however the language school I worked at gave me free lessons alongside my internship which was a huge bonus and definitely improved my Spanish. I also took on responsibilities alongside writing articles in marketing and administration which will be good for my CV.
Accommodation was probably where the experience fell down. Don't expect to get the full package: a central location, other international students and a level of cleanliness. This isn't Adelante's fault, more the agent they work with and the pandemic that has reduced their pool of accommodation, but it is something you should bear in mind if you're used to living in "style".
However, I made lots of great friends and lived in an amazing city for three months. It's really boosted my experience and career and was a gateway into Barcelona.