Deadly tumor inside my chihuahua

Hi I'm Daning Rivera, I've recently found out that my 12 year old chihuahua has a tumor in his stomach. It can lead to his death very soon if he doesn't get the surgery and vetinerian care he needs. He also has a very bad ulcer in his left eye that needs care as soon as possible or it can rupture and he can lose his whole eye. I can't afford all of the medical fees on my own so I'd appreciate any help I can get. Our pets mean so much to us and we all want to do everything in our power to save them, he is my best friend and he helped me through rough times and it's my turn to help him. Anything you guys can offer will be VERY appreciated. Thank you and help me save this little man.