Personally I just have a markdown note in which every new heading is a new day. However, there are multiple ways how to approach this. I know of people who make a new folder/tag per year and create a new note with date and time within this year folder for every day. For subscription users there is also an implementation with a calendar view. Within this thread it is described how to enable this:

~https://old.reddit.com/r/StandardNotes/comments/zxob0f/daily_notebook/ (beware)~