Can I get an adjustment of status by marriage? How?

Have you tried applying for DACA? In the worst case scenario, you need to look into waiver options.

If you entered the U.S. unlawfully and without inspection, then further details, including the date you entered the U.S., whether anyone has ever filed some sort of immigration-related application for you before, etc. would be needed in order to assess immigration-related eligibilities, options and strategies for you at this time. It would be wise to engage an immigration attorney who, after learning all of the relevant information, could advise you about eligibilities, options and strategies and represent you in the application process. Some immigration law firms, including mine, offer legal services on a "flat fee" basis so that a client will know the total expense from the very beginning, and a few immigration law firms, including mine, offer an initial consultation free of charge.