Hi! since I was younger I have always been terrified of speaking in front of large crowds, and many times it has resulted with me having an anxiety attack but I am finally coming out my shell (a little at a time)

I still have the issue of whenever I am in front of large crowds or an uncomfortable situation I turn very red and sort of shake. In a month I will be expected to stand in front of around 200 people and give a speech. I really don't want to embarrass myself by going red even though these people are really accepting and kind. It also gets really hard to breath and I'm just overall really anxious for this

Any advice on what to do?