Using Cloud Convert and Google Slides, you can turn a PDF into an image and insert them into a Google Slides. Then, you can assign the Google Slides to students (Assign one copy per student!)
Link to install the CloudConvert extension
Here's another method to make your PDF editable without Cloud Convert. It uses the snipping tool on a Windows device (or your phone) and imports that into the Google Slide background.
I came across another method for students to be able to write answers on a PDF. However, it’s quite a bit more heavy on the student work side of things. It's really only something I think that middle and high school students could handle. Teachers could use this as well if they see a good purpose for it. I have enabled DocHub as an extension. Feel free to watch the video and see if it is something you feel you could use. If you do, I would suggest sharing this same video with students so they know how it works.
https://www.youtube.com/watch?v=9Ah8O3wrnS0&feature=youtu.be
Here is the link to install the app: https://chrome.google.com/webstore/detail/dochub-edit-and-sign-pdf/adgncicbhbjfpijkdmbijninnhnmiblj?hl=en-US