Why is there oil in my 2014 Ford Fiesta?

First off I want to tell what happened before and up 2 the point that I found out I had oil in my radiator( it's milky by the way). I had been driving my car and did not kno it was low on oil. I assumed that's since it was a new car the oil should have been at good level until I got my next oil change. I was proved wrong and to my disappointment my car turned off on me one day and at the same time decided 2 show the low oil indicater light. I guess it's designed to show you when you hav hardly any oil so you can put money back into the economy for the repairs. Anyways I went and got the oil and put about 4 quarts in and then cranked it up. A lot of white smoke was coming out the muffler at this point. I was told I could burn off the excess oil by running the car so I attempted that. I drive my car for about 20ft and the engine started to turn off. I guess I had put 2 much oil. So I had the car towed to my house and I drained the excess oil. Drove the car and it was fine but when I parked it I heard my resavior water boiling so after it cooled down I opened the cap and there was milky substance instead of my coolant. I checked it and It's oil. So now I'm confused as 2 how that happened? Could the excess oil hav squeezed out into the cooling lines? What are all the possibilities? There's no warranty on my vehicle so please don't tell me 2 take it 2 the dealer. And I'm broke so I need an affordable solution if that's possible? Also right before my car turned off i smelt burns oil.

You have a blown head Gasket most likely but who can tell after you messed it up. This is going to be $$$$ cubic dollars. You talk a lot.

We didn't need anymore that the first two sentences. You have a blown head gasket. Do not drive the car any more!

Blown head gasket, pure and simple.

Please see a mechanic. You are working on a car and you have no idea what you are doing.

Engine oil in the cooling system means a head gasket leak.
It could also be automatic transmission fluid in the cooling system, if you have an automatic transmission cooler inside your radiator, like most cars.

Engine oil is usually tannish or brownish, looking like a milk shake.
Auto transmission fluid is red tinted, usually.