Just a question that popped into my head, how were the old and new testaments put together with all the different chapters? Was there one specific person that put it together?
This is an immense question, better broken down into smaller questions about specific PARTS of the Bible.
The "Bible" as most understand it is a complex compilation of tons and tons of various texts that have each undergone their own literary formation history. E.g., even just the 'book' of Isaiah has an insanely complex authorial and editorial history before it come into the form that is found in the Masoretic text...
Your question is, at its heart, geared towards conversations about canonization. Canon is a post-biblical idea where various texts were selected as authoritative and other texts were labeled as non-authoritative (considered 'apocryphal,' or 'pseudepigraphical'). The canonization process for the Hebrew Bible (aka, 'Old Testament) probably sometime during the 2nd c. CE, while the NT canon utilized by the Protestant churches was first proposed by Athanasius in 367 CE.
Chapter and verse notations were not put in until much, much later (like, a thousand years later).
why do people think it happened at the council of nicea?