Is it permissible for a user to earn money by clicking on advertisements for other companies, knowing that the advertised companies and the advertising company approve of this method of attracting visitors?

It is not permissible to engage in this transaction except after ensuring that the advertised websites are free of prohibitions. This is because a high number of visitors is considered a form of support for them, and it is not permissible to assist in spreading evil, based on the Almighty's saying: (And cooperate in righteousness and piety, but do not cooperate in sin and aggression), and the Prophet, peace and blessings be upon him, said: (And whoever calls to misguidance will have the same burden of sin as those who follow him). If the websites are permissible, then there is no objection to that. However, if they are prohibited (such as pornographic websites, or those that sell alcohol, or usurious banks, or gambling sites, or proselytization), then this work is not permissible.