To become a president, you need to follow some rules. You must be at least 35 years old, be born in the United States, and have lived there for at least 14 years. This is called the "eligibility criteria.".
Next, you have to run for president as a candidate for a party, which means you have to join a party and convince the members to choose you as their representative. You have to participate in debates, make speeches, and answer questions from reporters.
After that, people in the United States will vote for you. The person who gets the most votes, called the "popular vote," will become the president, but the president is really decided by a group of people called the "electoral college." This group is made up of people from each state, and they vote for the president based on the winner of the popular vote in their state.
If you win the electoral college, you are officially declared the winner and become the president of the United States!