One question

Hello. I need to know this: Is incorrect use this "I got to..." instead of "I have to..."? Is correct to say "I've got to..." Can I say "I got a question"?

Thanks in the advance.

"Have" and "get are often interchangeable. There are some expressions where one is uses rather than the other. 

"I got it!"

Se dice frequentemente cuando tenés un idea.

(Cuando descobrés algo o agarras algo, un acontecimento)

"I gotta" es mas comun que "I've got to"

Mas se puede decir "I've got to go" frequentemente en inglés.

"I have it"

(já tenés algo, como estado de propriedade.)

Ambos son usados como "dever."

Ese és mas formal que "got", si el profesor está sendo estricto.

One question

Hello. I need to know this: Is it incorrect to use this "I got to..." instead of "I have to..."? Is it correct to say "I've got to..." Can I say "I got a question"?

Thanks in the advance.

Hello. "I got to..." is incorrect. It will be understood and some people say this, but it sounds uneducated. Say "I have to."

It is common to say I've (I+have) gotta (got+ to)...(in speech) and also common to say "I've got to" (in speech) like you said.

"I got a question" or (I've got a question) is something we say in speech as well, and I think it's correct, but "I have question" sounds better in both writing and speech. I say both of these interchangeably in speech, though.

One question

Hello. I need to know this: Is it incorrect to use this 1"I got to..." instead of 2"I have to..."? Is it correct to say 3"I've got to..." Can I say 4"I got a question"?

Thanks.

1 is often heard in the vernacular. It is considered (by examiners, English teachers etc) as a wrong way to say 2. 2 is right. 3 is good to me (I don't know what examiners etc say on this one). 3a (a slight variant) is much safer: "I have to..". Similarly 4a: "I have a question.".