The official form
Scouting America publishes the form. Pack 13 links to it instead of keeping a copy, so you always get the current PDF. Part A is the consent. Part B is the health history. Part C is the physical exam.
Meetings, day events, and weekend trips under 72 hours use Parts A and B. Camps and other events of 72 hours or more also need Part C.
Download the PDF and fill it on your computer. Save that file so you can update it and print a fresh copy when the pack needs one. A form filled in by hand is harder to keep current.
Both buttons open a PDF from Scouting America in a new tab. The Annual Health and Medical Record page explains which parts you need.