I have found out that if someone sent me a pdf, I could also use an online tool and be able to fill it in by typing.
Here are the the easiest way:
1. Open PDF document in Adobe Acrobat Reader
2. Click on the TOOLS option
3. A Text option will come up
4. Point it to where you wish to type and start typing
5. Save and use
For the third way, you need to be tech savvy, but you can find more on that way How to create fillable forms with MS Word 2010