I think that Instagram will be more interesting for teens and people under 27 (approximately). Instagram is full of various dynamic photos, as well as stories from different clubs or other vacation spots. This is very attractive to the teenager. Facebook is a more self-sufficient platform, where news from all over the world is often posted. There are a lot of different sad posts, as well as posts about problems that encourage people to think. In general, it is wrong to compare these two platforms as they are designed for completely different purposes. Regarding JessyLie's comment - I don't think buying followers is a good idea. After a certain time, most of the accounts that follow you will be banned. It is better to use various services like
https://sharemyinsights.com in order to monitor which posts your audience likes the most and develop in this direction. this way, you can quickly find exactly the audience that will be happy to follow you.