I will supply five words to get you started: calamity, calculate, canister, capacity, and cardinal.
completed
Columbine
chartist
Daffodill
diligent
isogloss
Of course, there are many 8 letter words that begin with the letter Y. One is yardwork. A word that is 10 letters long and starts with an N could be nauseating
deserted?
part??????
Try the word Flotilla.
Advanced
yes, smoothly has 8 letters and starts with s
Powerful.
A bird that has 8 letters and starts with s is: starling or snowy owl.
The first word is probably Grateful not enough info for the second word.