In order to cite references,
1. Create a separate bibliography file ending with a .bib extension within your LaTeX project. To do so click on the New File
icon on the upper-left corner of the screen.
Then, enter your file name.Your bibliography file must end in .bib. (The default file extension in LaTeX is .text).
Once you create your file, you can add references to it in the BibTeX format.
The easiest way to do that is using Google Scholar.
1. Click on the Cite link under the article title
2. click on BibTex
3. This is the BibTex info from Google Scholar. Copy it.
4. And paste it into your references.bib 
1.To cite in text add the command ~ for a nonbreakingspace followed by \cite{}
2. Go to your references.bib to get the key for the reference as highlighted in the example below.
3. Back on your main document,
a. Add the article key in the brackets after ~\cite{blum2021prompt}
b. Add a bibliography style, i.e. \bibliographystyle{plain}
c. Tell the document where to look for the key i.e. \bibliography{references.bib}
4. Click Recompile
Select the references you'd like to add to your file and then click the Share button in the top menu.
Then choose Export References
Next, select Format BibTeX and click export.
Then in Overleaf, click on the upload button at the top of the left hand column.
The file is uploaded. Copy and Paste the article key (highlighted below)
In your main.tex, cite your source. If using multiple bib files, they are listed in the same command as demonstrated
Bloom demonstrates this process~\cite{blum2021prompt}.
Lucas has a different explanation~\cite{RefWorks:RefID:717-marie2020negotiating}
\bibliographystyle{plain}
\bibliography{references.bib, export.bib}
