How to spell PUNCTUIO correctly?

If you meant "punctuation", that would be the correct spelling. Other options might include "punctual" or "puncture", depending on the context. If you're not sure about a word's spelling, a quick Google search can help prevent common errors like this one.

• Punctilio He was a person of great punctilio and always followed the rules of etiquette to the letter.
• Punctual The train always arrives on time because it is known to be punctual.
• Puncture I got a puncture in my bicycle tire on my way to work.

Excatally

• exact
• exacted
• exactingly
• exactly
• exacts
• executable
• exotically
• extol
• inexactly
• oxtail