1. How can I get mental peace? 2. How can I attain God? 3. What is the way to success? 4. Is it possible to earn a lot of money? Please let me know.

You have wished for ‘Dharma’, ‘Artha’ (wealth), ‘Kama’ (ambitions) and ‘Moksha’ (God). Srimad Bhagavatam says that all these four can be attained by performing service to Lord Sri Hari.
Chanting the Mahamantra and pleasing the Lord is the easiest way to serve Sri Hari. So start chanting right away and attain these four very easily.