I've always been a huge supporter of mental health issues because they can and do affect so many more people than you think. Your neighbour, the one smiling brightly and cheerfully, they could be suffering inside and hiding it. Your boss could be suffering, and that could be why they're a little harder on you. Your mom, your brother, your father, your sister - Anxiety isn't a death sentence, but to someone suffering it can feel like it. Please remember to try to offer support without simply dismissing how they feel.
You can help someone suffering with anxiety just by being there. Listening to them talk, because even though they're worried about things you know to be not true (they are aware their fears are irrational too, but they just can't control the way their brain handles this), just listen, support them when they're having a good day, support them even more when they're not. Try not to constantly talk about their anxiety, often that little bit of normality can help them feel closer to calm. At the same time, try not to get upset with them if they're having a particularly bad day. Try not to let their anxieties pull you in as well, because you need to protect your mental health as well as support theirs.
Lastly, I wanted to share this video of Kristen Bell talking about her struggle with anxiety and depression. Often times people can suffer from both, which makes their struggle even harder for them to deal with. Anxiety and Depression can and do happen to everyone, don't feel alone or "crazy". You're you and you're allowed to feel how you do. Just know there are many people out there suffering from the same things and we are just a few key clicks away for support.