You can to the right place to learn! Look around the threads and absorb everything you can. Educate yourself here on everything you can pertaining to your interests. All the information you seek is here on the nexus.
Dosage... start low and work up to a place that feels right to you.
Next Level... is entirely up to you.
Light doses are fine.. dip your toes in and go into deeper water when you are ready. Take your time!
Changa is good. It can provide a longer experience when it contains harmalas. Enhanced herbs can be much easier to ingest through a bong as vaporizing can take some practice.
As I mentioned, research and find the information you are seeking here. Go into chat and ask questions if you need.
Good luck my friend! Have fun and take it easy!
"In the universe there is an immeasurable, indescribable force which shamans call intent, and absolutely everything that exists in the entire cosmos is attached to intent by a connecting link." ~Carlos Castaneda