Are there any exercises or things I can do to calm my anxiety?

Running is a great way to overcome anxiety. Running is often related to a runner's high where the prolonged exercise releases dopamines and lowers blood pressure.

Yes, lay down on the bed with no pillows and breathe deeply to the count of 4 and exhale to the count of 6, this helps in oxygenating your brain

there are plenty of breathing exercises which you can use to help lower your heart rate and calm youself down. one i i use whenever i am feeling anxious about something is to breathe deeply in for about 4 or 5 seconds, then hold that breathe for a few seconds, then exhale slowly, and wait for a few more seconds before breathing in again

Something known as "Triangle Breathing" really helps me. It's where you try to just focus on your breathing so you calm yourself down and then can assess the situation properly. You want to breathe in on a 3 second count, hold your breath for a 3 second count, then exhale on a 3 second count and repeat until you feel a bit better. Practicing this technique while in a tranquil environment or situation is key though, for it wont work if you don't.

I have found mindfulness meditation very helpful for me in the past. It helps to relax your mind and your body and to focus on being in the moment and not thinking about the future or the past. You can start by simply meditating, sitting in a quiet room, feet flat on the floor, hands in your lap and you eye closed and just focus on your breathing and the way your body feels. Focus on how seperate parts of your body feel. If this isn't working for you try focusing back on your breath. This is only 1 technique and i'm sure if you even google or youtube, there will be materials that can help you get through the meditation. I hope this helps you, as it has helped me in the past many times.

Take a deep breath. Look at or think of the stars above you and understand that there are much bigger things.

i have a severe anxiety and i have few things i do to calm myself like running/or just exercising in general, listening to my favorite music and holding my breath then exhaling slowly

7 cups has many resources for coping with anxiety! When you get anxious, try to take deep breaths. Listen to music, play with a family pet, read a book, take a hot bath. Do things that make you feel safe and calm your nerves a bit.

getting participated in the most important activity you can do for yourself to keep yourself from anxiety

Of course, yoga is a brilliant way to calm yourself and feel free and like you understand your own body more, which can help grow your confidence. You can try and build yourself up to go to a gym or another public place where you can workout, which can increase your confidence and reduce certain anxious fears.