How can a young person serve Islam and offer what benefits the religion?

Serving the religion encompasses many matters, among them: learning the شرعي (Shar'i) rulings and teaching them to people, adhering to the commands of the religion, inviting to Allah through all available means, supporting Muslims and supplicating and empathizing with them, and spending wealth in order to exalt the word of Allah. These areas vary according to the need in each country, and any of these actions performed with sincere intention is considered a service to the religion.