Help Mimi Pass Peacefully and Painlessly

My name is Xavier, and my pet's name is Mimi.(she’s more like an older sister then a pet)She is a very sweet and beautiful cat. She has lived a long and happy life with us for 21 years (100 cat years). She is having trouble breathing, eating, and moving in general. I’m trying to raise money to get her put down so she can pass easy and painlessly, as well as pay for a cremation.

Anything helps. God bless.