So, what exactly "do' or "be" or "have" mean?

When the verbs 'be, 'do' or 'have' are used as in a rather functional sense.. do they still convey any meanings to themselves?

What I mean by that is.. say if I use the verbs to make questions like..

Am I handsome?,
or Do you like sports?

Do you use them (am do ) just to make a question, or do they still have the same meanings like (Am ~ equals to or status of nature, and do ~ act in a certain way..)

I'm asking this because...I know you can make those questions without even using those verbs by just raising your tone at the end.

Like.. Me handsome?
Or.. You like sports?

I know they give a slight different..nuance to the whole sentence, but it can be done nevertheless.

Maybe I shoud've asked why you guys change the word order when asking questions.. because I don't in my native tongue.

When I was first learing English, the teachers taught the language as if it's some kind of mathematical formular. Like.. ok if you want to make that sentence as a question, you have to put "do" in front of the sentence and omit the original verb without telling us what the "do actually means.

Can somebody help me please..

Yes the same meaning follows when they're used in isolation.

Am I handsome? Am I? Answer: I am.
or the full sentence: Yes, I am handsome.
The same can be formed from... Are you? You are. Is he/she? He/she is. Are they? They are. Are we? We are.

Do you like sports? Do you? Answer: You do. (I'm answering for you)
or the full sentence: You do like sports. Or simply: you like sports.
The same can be formed from... Do you? Does he/she? Do they? Do we?

Like.. Me handsome?
Or.. You like sports?

Yep both of those are correct.

Only in speech.

You're right, "do" is kind of an interesting word when used in this auxiliary sense. It has no meaning of its own--like somebody said, you can say "You like sports?" and the listener will understand. But normally, it's just a question marker, like "est-ce que" in French or "ma" in Chinese, something you can just tack on to a declarative sentence to make it a question, or a negative marker, like "ne...pas" or "bu", something you can tack on to make an affirmative sentence negative. In that sense, of course, it can't be removed, even in colloquial speech.

What's more distinctive about the English "do" is the way you respond to these so-called "yes or no" questions. It provides an easy way to answer a simple yes or no question without going to the trouble of repeating the verb. This is mentioned above too.

"Do you like sports?"
"Yes, I do." or "No, I don't."

There's no equivalent in French (you'd have to say "oui" or "non" tout simplement or repeat the verb, "non, je les aime pas"), and the only equivalent I can think of in Chinese is "shi/bu shi"--"Ni xihuan waiguo dianying, shi ma?" "Shi, hen xihuan."

I know this probably isn't interesting to anyone else or even helpful to the original poster, but I just thought I'd write it down anyway.

And...

The socially correct response to "How do you do?" is "How do you do?"

Lovely, isn't it?