Buy a used physical copy for €5 on eBay or Medimops. Scan it yourself using a duplex scanner. This is legal for personal use (in most jurisdictions) as long as you don’t distribute it.
Many national libraries (e.g., Onleihe in Germany, Austria, Switzerland) offer free digital loans. If you have a library card, you can "borrow" the Schritte A2.1 PDF for 7–21 days. It automatically expires—no late fees. schritte a2 1 pdf
If you are learning German, you have likely come across the popular textbook series by Hueber Verlag. A common search among self-learners is for a "Schritte A2.1 PDF" —a digital copy of the first half of the A2 coursebook. Buy a used physical copy for €5 on eBay or Medimops