Start taking initiatives, unmute your mic and do give your opinion.
Be confident of what you are speaking, if you feel you would be wrong prepare for the lecture beforehand.
Know that you will ace everything, slowly start somewhere. Push yourself.
At the end of the you are only the one who can help yourself...if you won't succeed in life these people will not see excuses but your results.....try to cope with your anxiety then you will shine......its better to start than to regret in future....remeber you are your own hero in your life don't let that position down......its seems difficult but it's much easier when you will start....if you are confident trust yourself with your answers and will full determination say it to the class