As @Justin_Barrett said, you sadly can’t do this with the Page Designer block, but you might want to look into the Formstack Document block, which requires a paid Formstack account and enables you to create Word & PDF files from your Airtable data.
Alternatively, for a cheaper solution, check out Integromat, which lets you create Google Docs from your Airtable data that can also be saved as PDF files.
(Integromat also supports Formstack Documents as well.)