DSGVO Privacy Policy Help

Hello everyone. I am a relatively new docebian and as a lone fighter I am currently building a B2B learning platform with docebo. My current challenge is to develop the EU DSGVO/GDPR PP. Due to our focus on B2B (and later b2c), the topic is extremely relevant. 
Has anyone here been in a similar situation and faced with this? Of course I know what data the user has to enter when registering, but what data is collected by the platform? How precisely does the information have to be specified in the GDPR? What about data that is collected during learning ("secretly" without further evaluation for the user)? How exactly do they have to be named in the PP? Or is a relatively imprecise description ala "When using the learning formats, your learning behaviour and learning success will be tracked") sufficient? When using which module, e.g. Teams integration, do I have to add something to the PP? 
I would be very grateful for experience, or even a best practice or sample. I already have legal support, but the better I can prepare documents, the better I can react to them (and work favourably ).