I know it can be confusing to know the difference between all the numbers representing the doodle generations.
F1 is basically the first generation of doodle. So 50% Retriever and 50% Poodle.
F2 is basically the second generation of doodle. So still 50% Retriever and 50% Poodle.
Where it gets more confusing is when you and in a "b" or two. To simplify, 1 "b" means a doodle was bred back to a poodle and "bb" means it was bred back to a poodle again. The more poodle the less chance of shedding.
Here is a chart to help you understand in more detail. :)