You can pursue other means of financing to purchase a working farm. Community banks, rural farm loans and other regional specific financing is available. It might take a bit of research to find the right source.
If you are foreign national and want to obtain a visa, green card or citizenship, then you would be best to contact an immigration attorney. The immigration attorney specializes in helping foreign nationals integrate into American communities. They would be able to guide you through the necessary steps and the sequence in accomplishing each one.
Cash allows you to buy a piece of land. Earning a living from the land will depend if you bought wisely. Obtaining a permanent residency may not be impacted by the purchase of the land, that portion of your question would be best answered by an immigration attorney.
Brock Realty Inc.