How to allocate more RAM for pdf generation?

How to allocate more RAM for pdf generation?

I noticed that only 17 % of  CPU is utilized during PDF generation hence it takes more time to generate a document. I need to generate a single document as a requirement for a product which is large (nearly 350 MB). Is there a way to speed up this PDF Generation?

I also noticed a message ïn output view as below which has RAM 2048 M Bytes, I am not sure how this value is set

"Printed Document Generator Environment: Word 16.0.10730,  OS 6.2.9200, RAM 2048 M Bytes"