Hello, my name is...

안녕하세요.

1)(저는) 브라이언 스프리어입니다.

We write "입니다(ibnida)" and say "임니다(imnida)". In other words,  the second one is how to pronounce the first one.

You can skip the subject "저는", but writing it would be better.

Probably "Brian" would be "브라이언".

We don't make any blanks between "이다" and the complement(here, your name 스프리어).

e.g.

I'm a student.

저는 학생입니다.(O)

저는 학생 입니다.(X)

Alternatives:

2)저는 브라이언 스프리어라고 합니다.

3)제 이름은 브라이언 스프리어입니다.

Although the literal translation of "My name is..." is the third one, all of the three sentences are often used.

"은" and "는" are used when you introduce yourself, not "이" and "가"

제 이름은 브라이언 스프리어입니다. (O)

제 이름이 브라이언 스프리어입니다. (X) This sounds unnatural.

Hello, my name is...

안녕하세요.
브라윤 스프리어 임니다.

If you want to introduce yourself you should say:(이름이 Brian 입니다.)

Brian: 버래안

Hello, my name is...

안녕하세요.
(저는) 브라이언입니다.

Brian - 브라이언 (my opinion and the internet)

저는 - I (humble, with particle)

제 이름은 브라이언입니다.

저는 브라이언이에요.

제 이름은 브라이언이에요.

<em>"Thank you, one of my resources is a book called "My Korean" from Monash University. It taught me to use imnida instead of ibnida. I don't know what that's about. Would the way I wrote it be correct if I simply wanted to say "I'm Brian" instead of "My name is Brian"?"</em>

<em> </em>

First of all, discard Romanization completely from your mind, especially if you are even remotely capable of reading 한글. Forget what something sounds like? Go find some audio. You will not learn how Korean sounds through how English letters look. Furthermore, every letter in English makes so many different sounds, you could interpret Romanization in a thousand ways.

입니다 is the only correct way to write it. Not ibnida. Those are English letters that do not tell me how it sounds or looks in Korean.

It is, however, pronounced "임니다". Not imnida.

It seems very intuitive to me. Making a clear ㅂ sound before the ㄴ sound is a bit difficult and odd. Spoken, it starts to naturally make a ㅁ sound. So it pronounced as such.

Do not ask why they don't just spell it that way then because why does English have silent letters? Why does each letter/symbol make so many different sounds? Why is the plural of house houses but the plural of mouse mice? I don't know what to tell you. Language is a living animal.