Pros
Can learn a lot but you can do the same from home as senior/ceo/management provide no help and specially ceo(who is also hr and manager) under whom you will work doesn't have any technical knowledge. And on top he will expect ridiculous feats like creating model with 90% accuracy while Google can best do 70%.
Cons
No compensation if ceo/manager/hr thinks you underperformed. Which is always the case because his goals are so unrealistic. I haven't received the salary for the 2nd month of my internship. Not a good working environment. As I explained above manager doesn't know anything and sets unrealistic deadlines for projects. He always gives a week to complete any project to interns while I saw their 2 permanent employees work on single project for 2 months and still did not deliver even though they have most of the code written by a previous intern because that's how difficult the problems are.