how to connect with database?

I am developing a game for children, it basically consists of a character who explores the area of ​​the game, which contains certain points that when the player approaches provide an activity for him to perform (a calculation, the writing of a word, and things like that) ...). However, these activities must be random, and this is where my doubt comes in. Is there a way for me to register these activities in a MySQL database and the construct call randomly?

Do you have web hosting that can create MySQL databases?

From C3 you use AJAX to call a PHP script on the server that reads and writes to the database. There are a number of tutorials to help get you started.

If there are not very many activities, they could be stored in a project file within C3 (using an array or json) and you can randomly pick from that.