Depending on who you listen to, it will take over a year to get to Mars flying time. Mars is the goal for Musk. How to do it? Use the 6-decades-ago-developed atom-bomb rocket - https://newatlas.com/orion-project-atom-bomb-spaceship/49454/. Send the parts up into space, away from Earth, or to the moon. Put it together there, and launch it from there. No radiation problems from there, because the sun puts out much more deadly radiation than atom bombs. Of course, don't tell any government what you are doing. Get parts from any number of countries, so that no single country suspects. Launch SpaceX, with the parts, from an ocean platform if countries complain. Then put it together and Go!