The vast majority of people who use stainless steel cookware don't report any adverse effects in terms of flavors or smells. Some people say that their food tastes better when cooked in stainless steel, and some people say it doesn't make a difference.
There are a few exceptions, however. Some people find that their food picks up a metallic taste when cooked in stainless steel. This is most likely to happen if the pan is new or if it's not been properly seasoned. If you're having this problem, try seasoning your pan before cooking (you can find instructions online).
Another exception is if you're using a very acidic sauce or ingredient (like tomato sauce). In this case, it's possible for the acid to react with the stainless steel and cause a metallic taste. If this is a concern for you, try cooking your food in a glass or ceramic dish instead.
Overall, stainless steel is a very safe and non-reactive material, so you don't have to worry about it transferring any flavors or smells to your food. However, if you're concerned about it, be sure to season your pan before cooking or use a different type of cookware.