In all likelihood, you don't mean to be using \bibliography{apa}, this isn't bundled with a current TeX Live distribution and apa.bst which you are most likely using is more than 30 years old, pre-dating both LaTeX2e and the 5th if not also the 4th edition of the APA style. Probably, you want to look into the likes of apacite and biblatex-apa, and the questions How to APA 6th in LaTeX?, What is the relationship between natbib, apacite package, and apa document class?, and How do I use APA-style citations with BibTeX? on this site.
However, it does appear to be possible to successfully still use apa.bst. The fragment of the error message visible in your screenshot seems to point to a macro ending ...oncite{ as being undefined, looking at apa.bst it's almost certainly pointing to the \astroncite macro therein.
apa.bst is apparently meant to be used in conjunction with astron which provides the \astroncite macro, this appears to work, however astron is also 30 years old and not distributed with TeX Live, and the more modern natbib can be used in place.
\begin{filecontents}{bib.bib}
@article{Astekin.2018,
author = "Author, A",
title = "Paper",
journal = "Journal",
year = 2018,
volume = 1,
number = 2,
pages = 3,
}
\end{filecontents}
\documentclass{scrartcl}
\usepackage{astron}
\begin{document}
\cite{Astekin.2018}
\bibliographystyle{apa}
\bibliography{bib}
\end{document}
apalikevariants and specific apa. You may have to download thebstfiles. – FHZ Sep 28 '22 at 12:23apais a valid\bibliographystyle, but theapa.bstthat is available on CTAN (https://www.ctan.org/pkg/apabst) and that you will get if you use\bibliographystyle{apa}unless you are doing something special was written in 1992 and will most likely not implement current 7th edition APA style. It's hard to tell what exactly is going wrong in your example, we need to see the relevant.bibentry and we need all the code as copy-and-pasteable plain text, not as an image. (Note also that the error message LaTeX produces are actually more verbose, your editor truncates them). – moewe Sep 28 '22 at 15:44biblatex-apa. – moewe Sep 28 '22 at 15:45