https://foragerchef.com/how-to-make-beef-tallow/
This is my basic method for rendering beef tallow at home. You can use it, and the tricks I describe in the video for literally any fat you can possibly think of. Chicken fat, pork, lamb, goat, venison-it's all the same.
The most important thing beside making sure your fat is very fresh, is buzzing it with a handblender or otherwise making sure it's really finely chopped. This has a direct correlation to the cook time, and the finished yield.
Once you render some of your own fat the first thing you need to do is make some hashbrowns, fried or roasted potatoes. If you didn't know, Mcdonalds used to cook all of their French fries in beef tallow, for a reason. A lot of people use the same method to render tallow for soaps and lotion too, and this method will do that for you as well.