So, where do you start? Well, first, just try subbing yogurt for sour cream in your favorite recipes. It's a 1:1 ratio, so it's easy peasy. Then, experiment with different types of yogurt - Greek yogurt is a great choice for thicker, creamier dishes, while regular yogurt is better for sauces and marinades.
Sour Cream Substitute For Yogurt at Andres Lowe blog
And don't worry if it takes a little trial and error to get the hang of it - that's all part of the fun! You might find that you prefer the taste of yogurt in some recipes, but not others. But hey, that's all part of the cooking adventure, right?