How do I sign my digital documents?

Hi. My district is going fully digital in the next 2 weeks. I have been using canva and Google docs, but I cannot figure out how to digitally sign with ease. I have 600 students and give a syllabus to every student. A lot of kids sign each other's digital syllabi and turn them in. How do I just have students sign my already-made signable pdf of a syllabus and my signable pdf receipt? I need an app or something that has each kid sign their own or for me to quickly and easily see who has and hasn't signed them? Any expertise in this area would sure help! I have Canvas and Google classroom.<br><br>UPDATE: dropbox sign seems great but I can figure out how to bulk sign the same document. Can you help with that?