Hey,

Well,it depends on the meeting that yiu are going to attend. But there are few basics that are important no matter what meeting you attend.

• Dress Code: You need to be dressed properly in a formal attire for any kind of professional meeting.
• You nees to know what topic is going to be discussed upon and keep your points ready and be prepared.
• Always try to listen first and then state your point in the meeting.
• If you need to counter question then donot with a good and wise choice of words.
• Always write down important notes that you think will be helpful to you.

That's all the basics important beforw attending a meeting.

I hope this helps