First buy bitcoin and then you can start exchanging it to other coins in an exchage. One of the best which is bittrex.

Hello, I try to explain you what was not understood of the stretch goals,
something quite important was misunderstood.
The DomRaider blockchain is a project that a lot of people are working on, and it has many supporters, including people like Eddy Travia or Mougayar, people who believes in designing a worldwide auctions blockchain. Perhaps the word “worldwide” was not understood. Cryptocurrencies have become a way to make easy money, not a way to dream in great projects.
More people will receive tokens and more people will be involved in this "worldwide" blockchain. The DRT value will not be given by making it an elitist currency, but by making an “exchange currency”.
The more a coin is exchanged, the more its value increases. But you have to think long-term. This is the idea that animates the project, not the idea of making fast money.