On the value of doing nothing
We are driven to produce, to work and to create, not by our own inclinations but at least in part by the software that was installed in us by our culture. The discomfort one feels when nothing was achieved is an excellent point of entry to understand this.
No other being on the planet makes lists. We have to cut down trees, make them into pulp and then paper and then mine graphite to make the pencil and paper necessary to make a list of what we need to achieve to relieve the anxiety created by not doing anything.
Firstly, you are never doing nothing. Your breath, digestion and homeostasis are happening continuously, but because we have decided we are not "doing" those things they don't count. If even for a few minutes any of that ceased, we'd die - that is how important to us these processes are. But what's valued is not what you do easily, but what is hard. So we are forever trying to prove our value, often at the expense of the supportive elements around us - all the other things that don't make lists.
A paradox here: Why am I writing this instead of not writing? Do I expect my words will have an impact on you? The answer is I don't know, but my intention isn't to change your mind. I tend to look at writing in the same way I look at humming a tune. I don't hum a tune for any reason and I don't plan to hum, it just happens. If I tried to stop humming it would take effort, and writing for me is the same.
Is there a method to become more comfortable doing nothing? If there were, that method would be placed at the top of your list of things to do, and that list would be titled "127 steps toward doing nothing comfortably". It may take years to achieve doing-nothin-ness, and that's exactly what we are comfortable with because it will avoid the discomfort of actually doing nothing.
Consider when someone is listening to you. A good listener allows you to speak without interruption, so that you can formulate your ideas in the presence of an attentive silence. A good listener isn't waiting to speak. A good listener isn't "trying" to listen to you, or furrowing their brow, or influencing your communication with theatrical expressions of interest or shock. A good listener isn't doing anything, and their ability to

not do anything makes our lives better because we feel heard and accepted.
One more thing. Even our language makes it difficult to do nothing. Notice the phrase "do nothing". For nothing to occur, it must be "done". But a list does not have to be made, an intention does not have to be set. Nothing may happen, all on its own.