Here are some of the typical things you can do to prepare for a Newbie Session:

• Create a character on D&D Beyond.
  • All officially published races and classes are accepted. Please use "standard array" or "point buy" for your stats and select the "Equipment" option on the last step to ensure that everyone has similarly balanced characters.
  • Depending on the DM, they may have different rules or include/exclude certain content.
• Create accounts where requested. For example, you will likely need a Discord account and a virtual tabletop account (ex. Roll20).
• Test your hardware. For example, make sure your microphone is working in Discord.
• Double check your schedule and notify the DM immediately if you can’t make the game. Having players drop-out last minute may cause the game to be canceled!

https://www.youtube.com/watch?v=r1RxnZPELxo