By "yams" I mean the orange colored sweet potatoes sold in stores. They are sometimes called garnet yams or jewel yams.
You don't have to be exact with how many yams, beets and carrots you use. You can vary the amounts some. The color and taste may be a bit different, but it will still be delicious!
The scale I use allows me to put a plate on it, then zero it so I know that I am getting exactly 16 ounces or 8 ounces or however many ounces of food that I need.
You can omit the garlic if it is problematic for you.
See this blog post for more information on the Instant Pot.
Here is a link to an immersion blender if you aren't familiar with it. It is great for blending drinks, soups and sauces!