Create a new account with a payment option on the account
Go to Microsoft support, then to contact us
Once you are there, you should be talking to a bot
Proceed talking to the bot until it gives you the option to talk to a real person
When talking to the Microsoft agent send them this message “Im new to xbox, my friend told me that i was eligible for a free xbox live gold trial” (but switch it up every time so they don’t notice)
Continue talking to the Microsoft Agent until they give you a code