How do I use my phone to record my class lecture?

[AC Question]

I need to find the settings to allow my galaxy s6 to record just conversations and not video.

 

[B. Diddy]

Welcome to Android Central! It looks like the stock Voice Recorder limits you to a one minute recording: Samsung Galaxy S6 edge+ User Guide. Look on Google Play for a 3rd party voice recorder app that can record a much longer file.