How to use TCPDF library in wordpress

I would like to use the library TCPDF to create pdf. Specifically, I want to create a pdf after clicking a button available in every custom post type called Property. This PDF has to have Property data and author (who created the Property) data.
Thus, my question is: where do I have to put all the files of TCPDF library? Do I have to create a plugin?

Thanks!