>>2833098 (OP)
>passport
Depends on your country but if you are American then you go through the US Department of State website and look at the forms needed. You will need to set up an appointment and bring your passport photos (you can get these at Walgreens), proof of citizenship, required documentation, etc. I did this at a post office and had my photos taken there.
You can buy plane tickets through websites that sell them. As a rule of thumb, foreign carriers generally have better amenities than American ones on transcontinental flights. You will need a passport number, your name, and a form of payment to book a flight.
Since you are rich now, you can probably hire a luxury travel agency to handle all of these concerns for you. If you have a good credit score, you can also apply for a credit card with travel benefits and utilize those to your advantage.