Depends on what you mean by working with Access. If you simply(?) want to import data from it into your site's database, then you're probably looking at exporting the Access data of interest into a CSV file, then using some SQL or your database admin tool to import that file's data into your database (or creating a script to do so, etc.).
If you want to interact directly directly with Access from your site, I don't think PHP comes with any built-in support for it, so that would likely be a non-trivial challenge (or worse).