Anxiety (Vishada) is the starting point of the Gita. Krishna explains that we worry about things beyond our control. The core solution is 'Stithaprajna'—becoming steady in wisdom by focusing on the effort (Karma) and letting go of the anxiety of 'What if?'.
You have a right to your duties, but never to the fruits of your actions.
Feelings of heat and cold, pleasure and pain, are temporary. They come and go like the seasons. Learn to tolerate them.
Lift yourself up by your own Mind; do not let your Mind pull you down.
If you are preparing for a job interview, focus entirely on your preparation and your presence during the meeting. If you worry about 'Will I get it?', your performance drops. The Gita suggests your duty is the preparation, not the outcome.