So: Ich heiße. Du, sie, er, es heißt. Wir, Sie, heißen. Is that right? What about Ihr?
Yes, that's right. Also, "sie heißen".
"ihr heißt" - same ending for this verb as "du, sie, er, es".
Sounds like "yule ya" to me (on the slow speed). I do not hear any J sound at all.
In German, the letter J always has the pronunciation of English Y as in "young" in native words.
(And this includes well-assimilated foreign loan-words and names such as "Julia".)
What is this ß thing?
"ß" is not a "B" or "β" (beta)!
"ß" is used after long vowels and diphthongs (ai/eu/au/äu), and "ss" is used after short vowels.
What would I use for "They are called Julia", When referring to more than one person with the name name. Would that also be "Sie heisst Julia"?
No -- you need a different verb form for sie = "they" than for sie = "she".
"They are called Julia" would be Sie heißen Julia.
Because "bin" goes with the subject "ich"; you need the correct conjugation for "sie," which is "ist" ("Sie ist Julia" is correct). Using "bin" here would be like saying "She am Julia" in English. "Heiße" is also wrong for the same reason; you need "Sie heißt Julia."
(Also note that the letter "ß" is not a "b." If you're on mobile, you can probably type this letter by holding down the "S" key; otherwise substitute with "ss" (i.e., "heisst").)
Use ß after a long vowel or diphthong (ai, au, äu, ay, ei, eu, ey, oi, oy).
Use ss after a short vowel.
Whether a vowel is short or not is something you will have to look up in a dictionary if you do not know it already. For example, the vowel is Floß "raft" is long but the vowel in floss (flowed) is short; the vowel in Maße "measurements" is long but the vowel in Masse (mass) is short.
Sometimes Germans disagree about whether a given vowel is long or short; if both lengths are considered standard, there will be two standard spellings, e.g. Spaß and Spass for "fun" or tschüs and tschüss for "goodbye".
Could this also mean "you are julia" as in "sie heißt" as a formal form of "heißt"?
No. The formal form would be Sie heißen -- with capitalised Sie and with third person plural verb form heißen (like sie "they"), not with third person singular verb form heißt (like sie "she").
I got it right really heist the letter they use is not in the english alphabet
That's not correct -- if you cannot write ß, then write ss instead, not just s.
For example, weiße Würstchen "white sausages" are not the same thing as weise Würstchen "wise sausages".