You can substitute feta for ricotta in some recipes although it's not always a perfect substitute for certain recipes that call for feta or ricotta specifically.
Feta cheese is saltier than ricotta cheese and also has a more robust flavor which is sweeter and milder.
To balance out the extra saltiness of feta cheese you can reduce the amount of feta cheese you use by around 3/4 of the amount of ricotta cheese that is called for in the recipe.
You can also adjust the levels of sugar in the recipe.
Feta and ricotta cheese also both have a crumbly texture, which works well in baked dishes.
The salty and tangy notes of feta cheese also go well with savory ingredients and fruits.
You can also use feta cheese in cooked recipes where the flavors will complement the dish.
Ricotta cheese is often made from leftover whey in cow's milk, goats milk, or sheep's milk.
Feta cheese is often made from sheep's milk or a mixture of sheep's milk and goats milk.
Feta cheese is an excellent substitute for ricotta in recipes where you want a more pronounced and salty flavor.