Nervousness
https://www.google.ch/search?q=nervous
Synonyms for nervous
http://www.thesaurus.com/browse/nervous
The most important tool for reducing nervousness is exercise. Exercise allows you to reduce your nervousness because it increases production of relaxing neurotransmitters while simultaneously burning hormones caused by stress and tiring the muscles so that anxiety symptoms are less severe. https://www.calmclinic.com/anxiety/overcoming-nervousness
To reduce nervousness when you speak, give yourself
permission not to be perfect. When you make a mistake, keep going.
https://www.psychologytoday.com/us/blog/communication-success/201305/5-tips-reducing-public-speaking-nervousness