I picked most of the vocabulary from a list of the most frequently used 1,000 words in Italian.
The grammar patterns are also very common, and in fact are found in any serious language course, either written or in audio, in roughly the same order as in this course.
Understand the method to set your expectations: you’re not expected to use those exact sentences in real life, actually not even to remember them.
That would be rote memorization and is neither expected nor desirable.
After you add vocabulary and grammar patterns to your repertoire, your brain will know how to recollect them and put them together in sentences you’ve never heard before.