There was a lot of training that wasn't directly related work, However the training we had about our line of work was top tier
We were working on JAVA APIs.
What I like the most about the internship is that we got to work alongside four senior developers who we could go to whenever we got questions, and who provided up with really significant information, insight, and advice.
There were a few lunches and special activities throughout the summer which were enjoyable.
Be prepared to research a lot. No one is constantly looking over your shoulder, thus it requires a certain degree of autonomy. But the biggest would definitely be not to be afraid to ask questions, there are no dumb questions.
The advice that I would give to the next intern facing a problem would be to seriously try solving it once. If what you tried did not work, instead of stalling looking for a solution, would be to go explain the problem that you're facing and explain whatever you tried to do to solve it. This is how we dealt with the question that we asked, and they were always glad to help us.