Takani-sama
This is Kawaguchi Hidetoshi. This is my humble answer to the question.
In order to overcome fear and anxiety, I recommend that you first calmly and thoroughly observe the state of mind once.
Exactly when does such a heart occur, and can it be said that such a state of mind continues continuously while awake, all the time, or even when sleeping? Of course, it's not going on or going to last forever. If that is the case, the same fear and anxiety must have continued all the time from birth until death. In other words, fear and anxiety do not exist as an entity; they are “empty.”
Of course, even if it doesn't exist as an entity, that doesn't mean it doesn't exist at all. Also, it is impossible for such a heart to arise from nothing. It is always caused by some cause or condition, and in other words, it can be thought of as “good fortune.”
Therefore, by firmly grasping the cause or condition, if that cause or condition is somehow improved, it will surely be possible to somehow improve the occurrence of such feelings.
Simply put, for example, when you're immersed in something fun as a hobby or when you're relaxing and working on something you're good at, such a sense of fear or anxiety probably doesn't occur because it has flown away somewhere. However, in the current situation, this is probably what will happen when you start thinking about work.
For one thing, I think it would be good to be able to suppress and eliminate feelings of fear and anxiety by gradually applying the method, situation, stance, and attitude of mind when there is no fear or anxiety when doing something.
Anyway, I hope you can understand even a little bit just that fear and anxiety can be easily suppressed or eliminated by changing the causes and conditions.
Please also refer to the contents of the Zen question “Daruma Anshin,” which is a humble answer to the following question.
The question “If this heart doesn't exist, will that heart move?”
http://hasunoha.jp/questions/380
Kawaguchi Hidetoshi Gassho