I second cal! Also I find bsdmainutils’s calendar quite amazing in its simplicity

Haha, I talked about my bullet journal approach, but there is one time I always use cal... When I've resigned from a job, I'll always the output from cal, format it to full page in word in Courier, and grey out all the non-working days, and days before now and days after my last day in the job. And then print it out and cross off each day until I leave like an advent calendar! I've had this ritual for the last 6 jobs, going back to the early 2000s when I quit a job I really hated and literally looking forward to crossing off every single day was what kept me sane in the (3 month) notice period.