how do I make each heading a specific format?

[unkempt mortar]

You can use the heading function directly instead of the "=" symbol

?render ```
// Set default heading to 1., for example
#set heading(numbering: "1.")

= Default heading numbering

#heading(numbering: "[1]", "Heading 1")
#heading(numbering: "(1)", "Heading 2")
#heading(numbering: "A.", "Heading 3")