Hi thank you for writing. This is the most commonly found form of anxiety. The healthy way to deal with this concern is by counselling through which coping techniques can be discussed and practise which will help you in a long term basis. Medications helps deal with general symptoms of anxiety which you have mentioned but would not make you a confident speaker.
Next Steps
Meet with a psychiatrist for anti anxiety medications. The more effective recommendation is to meet with a psychologist for counselling.
Health Tips
Meantime use mental imagination to imagine yourself present well. Stand in front of a mirror and practise the presentation. Practise in front of your friends or people with whom you are comfortable with. Use breathing relaxation techniques before going into the stage.