Frying only one side of eggs on a pan
There are three ways I know of to cook the egg all the way through without turning it:


Break the egg into a hot pan and turn the heat down, wait until the egg is cooked all the way through - this would probably be considered over-cooked sunny side up.
Break the egg into the fat left in the pan, or the fat that has been put into the pan (there needs to be a lot of it), once the bottom firms up a bit, use the spatula to sweep the hot fat over the top of the egg, cooking it on top with the hot fat while the bottom cooks from the burner/fire whatever.
Break the egg into the hot pan then cover the egg(s) or the entire pan with a lid and turn the heat down a bit; this will steam the eggs, cooking the top and the bottom at the same time - this is called smothered eggs.


All that being said, understand that undercooked and raw eggs are eaten regularly by many people; some examples are Caesar salad dressing, raw egg in milk shake (protein booster), steak tartare, sunny side-up eggs to name a few.