Can I ask something?? 

When referring to yourself, "I" is always capitalized

Like any other people person who is learning another language, sometimes, I wish I could express my opinion seriously with by using words like. 

Make sure you capitalize the first word of every sentence.  Also, since the person you are talking about is doing a continuous action, you should use the present continuous form, i.e. "is learning."  Finally, remember this pattern: "To do X by Y," where X is what you do and Y is the method that you use to do X.  "With" is not the correct word to use here.

It would make me looked wisdom wise, like I have many a lot of information.  They would think of me as a... high class man.  Do you know what I am saying??

Like using a metaphors. you know??

So, I just want to find out where I can learn the deeper meanings of words or idiomsdeeply. but However, I don't know how to find where they are this information.

Never start a sentence with but... try 'however' instead.

Do you know or can you recommend somewhere else where I could learn something these things??

"Something" is too general.  "These things" makes more sense because it is more specific.

I know how you feel.  I often feel like I sound like an idiot when I speak in a foreign language, and cannot express my true intelligence and personality.  I often feel like even though I can communicate information, it is impossible to communicate my true self.  잘했어요! 화이팅!