It’s not as complicated as you think it would be, by reading the sentence you look at key words that would help out like “used to” or “one day”, If you pay attention to these then you should be able to determine the past and present tenses with the given words and use them correctly
Top:
1. can
2. can
3. were
4. could
5. able
6. to
7. been
8. can/could
Bottom part:
1. have been able to
2. can
3. couldn’t
4. will be able to
5. be able to
6. being able to
7. were quickly
8. couldn’t
9. was able to
10. could
Hope this helps