Looking for a plug-in.Please help if you can.

I’m trying to find a plugin that will allow me to select PDF files. I’m trying to re-create the one that I have on the website below that was not created under word press. For the life of me I cannot find something like this. It doesn’t have to be exactly like this so if you have any other suggestions I would be willing to consider using that plug-in as well.

https://welchbrothers.com/precast.aspx