DMing from a PDF

I am considering using Roll 20. I have a PDF of the module I am using. Can I upload the PDF straight to roll 20

There are some things you can try, depending on what you mean by "upload the PDF": You can drop it in as the page of a handout, but that will only be a "one page at a time" method.   You can select the contents and copy paste them into a handout, but that might only give you the text.   You could probably print the PDF to a local webpage, load it in a browser, then copy paste that and get the images and paste that into a handout, and that might work... not really sure.

PDFs can be uploaded but it will be one page at a time and each page will be converted to a image format.

You can also just have the PDF open on your phone or another computer, or another window, and DM verbally from the PDF just as you would at a table at home if you have the PDF.  You can use Roll20 to give you abilities like voice chat, text chat, webcam, long distance players, online dice roller replacement for physical dice, and there is a large collaborative whiteboard where you & players can draw maps or illustrations while you're playing, or in advance.