You can set the course's time limit for solving puzzles/reviewing under course options.

This lets you set a value between 5 seconds and 600 seconds of how much maximum time you want Chessable to give you during the Quiz. The default is 30 seconds for most courses and 60 seconds for some. You are free to change it to whatever you prefer. Simply enter a new value and click save!

You can also click on the infinity sign (∞) to disable the timer completely.