Problem with adding references to my thesis

Question

I am writing my thesis in Overleaf and on compilation it gives me a warning, which says: Using fall-back BibTeX(8) backend: functionality may be reduced/unavailable. I understand it is because I am using BibTex as my backend instead of Biber. However, my problem is that after the file is complied, it only shows me one of my references and not the other one.

Example of my document is below:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[backend=bibtex,style=authoryear,natbib=true]{biblatex}
\addbibresource{References.bib}
\title{problem with references}
\author{abc }
\date{August 2019}
\begin{document}
\maketitle
\section{Introduction}
\printbibliography[heading=bibintoc,title={References}]
\end{document}

Is there any way I can use to show all the references? Note: In particular, my file does not show any references with a template of @misc

Edit: I forgot to add the \addbibresource{} to my example here. But it is there in my file. I didn't have any resources cited in my main.tex file. When I compile the file, it generates one of the resources on its own. However, when I add \cite{Reference1} \cite{Reference2} at the end on my main file it prints both of my resources. But it prints both of my references twice. First with their whole description and then just their title. I'm not sure how can I solve it.