During my first job after I worked with young people from around the country and we compared notes. This is my understanding of the regional names for carbonated "soft" drinks (like Coke) in the US.
In the Western US it is called "soda". Maybe "soda pop" on occasion. And people do call it a "soft drink" too. I am a Westerner myself and this is what I am accustomed to.
In the Midwest and North it is called "pop".
In the South it is called "Coke". But as LP said here Coke can mean any type of carbonated drink not necessarily Coke (aka Coca-Cola).
So a person in the South might go to a restaurant and say they want a "Coke" and the server would ask what kind of "Coke" and they would then say a "Coke" which means that want the Coke drink (aka Coca-Cola). Or they might say the type of Coke they want is Sprite. That confuses me and I have rarely heard it with my own ears but am assured it happens regularly in the South.
And yes as LP said, sometimes you hear the term "fountain drink" which might be at a fast food place like McDonalds. And it means the same thing as all the above.
I have traveled to Asia, Africa, South America and Europe (never Australia yet - hopefully some day!

) and notice that most countries have a much smaller selection of carbonated drinks than the US. It is common to see only one or two. Coke is everywhere I have ever been and is often your only choice for a carbonated drink. Sometimes you see "Fanta", or a Sprite-type drink.
The selections in the USA for soft drinks must be overwhelming to internationals. Further, the USA has more selections of
everything. We really have too much choice but that is another topic.
For carbonated "soft" drinks we have:
Coke
Pepsi (a Coke competitor)
7-Up
Sprite (a 7-Up competitor - I cannot tell the difference)
Mountain Dew (like the previous 2 but with caffeine)
Sierra Mist (another 7-Up competitor)
Root Beer (which is not beer at all and comes in numerous brands - A&W, Barq's and Mug to name just 3)
Dr. Pepper (my
favorite by far - no real competition)
Orange Crush (an orange flavored carbonated drink)
Plus MORE
PLUS variants of the above for zero calorie "diet" and zero caffeine. It takes an entire aisle at the grocery store to contain it all, LOL.