First, let me welcome you to FT and the Marriott forum in particular. Spend some time and look around. There is information on just about anything to do with travel and points. ^

Second, while I don't have a "code", if you live in NA or the UK, you can apply for a Marriott branded credit card. Those come with enough night credits for Silver status (which will also help to reduce the needed number of nights for Gold/Plat as well.)