I don’t know, I’m not an expert on the subject.  Let me check Wikipedia...
assistant
For your best results, it is recommended to use the correct quantity of cannabis to create a joint of equivalent size and weight as the cigar you are using.
assistant
I need help rolling a joint
user
No problem, here’s some Google results with your search phrase:

http://www.wikihow.com/Roll-a-Joint

https://www.decalmag.com/how-to-roll-a-joint/

https://www.weedguys.com/420/how-to-roll-a-joint/

Can I suggest an additional search term to help with your question?
assistant
How much weed should I use?
user