I use BibLaTeX with the following options: \usepackage{biblatex}[sorting=none,backend=biber,style=apa,citestyle=numeric-comp], but it still generates my citations in a weird order, which does not follow the order in which they are cited:
I have tried to modify it several times but can't get it to work. I've even removed aux files several times now.
In the question you have the package options after the package name. That is the wrong order. In \usepackage{biblatex}[sorting=none,backend=biber,style=apa,citestyle=numeric-comp] the options will be ignored. You want
\usepackage[sorting=none,backend=biber,style=apa,citestyle=numeric-comp]{biblatex}
for the option to be picked up correctly.
Note that each package should only be loaded once, so double check that no other bit of your code loads biblatex either directly or indirectly. Templates you can get off the internet are notorious for making it hard to figure out which packages are loaded where.
As discussed in the comments, APA style does generally not really mix well with other styles. It is a fairly complex implementation to stay true to very complex requirements. For now it is probably better to load biblatex as
\usepackage[backend=biber, style=numeric-comp, sorting=none,]{biblatex}
Alright, found the solution thanks to a friend. Had to add \PassOptionsToPackage{sorting=none}{biblatex} before the \documentclass
Something about a package overriting stuff
sorting=none. But theapastyle should generally be used without other options, so it's not recommended to mix it with a differentcitestyle.