I'm love my fiancé and I want to get marry to her for love and fixing her papers but I want to know how long will it take to get her papers fix and she is from Mexico

Where are you at, US, Canada, Cuba ? Where is she living now. Guessing you are in the US, getting married is not a promise of citizenship,

1. Did she change her visa to a finance visa before you got married ?
2. what type of visa is she on now.
3. assuming she is here legally, she will apply for a change in her visa status

4. if she is in US illegally often she will have to return to Mexico to reapply for a visa to enter the US. It can take months and longer.