How can introverts become comfortable in social situations

Anyone experienced this when you are at your desk and working suddenly these rush of thoughts starts to trouble you like some of your colleagues watching you and judging because you are not opened up to them and didn't say single word in the morning when you came for a work it is like as if you are a robot just come sit on chair start to work.After sometime you start to overthink and suddenly your mind wants you to leave the place and it triggers a panic attack and you are unable to concentrate on the actual work.. What are some of the hacks that you become open up to your colleagues and at least say "Hi!" or "Good Morning" with some confidence/courage and become comfortable in the team.