I've got an almost 4,000 line file with the same kind of stuff for work, every day since 27th March 2019. It includes not just what I did, but also things like IDs for data in various environments so I can go straight back to what I was doing if needed.
At the end of one day I add the entry for the next day (mine is Markdown and the latest is at the top) to remind me of things I've discovered that will be relevant, and I update the current day's entry as I go.
I use Markdown because I use bullet lists almost exclusively (brief, with nested children for detail). It's also great for short code blocks.
Having seen my file during remote stand-ups I now have several colleagues doing similar. There really is no need for anything fancier.
But remember - frequent dated backups and if possible (and you're an employee) use networked drives so you are enrolled in corporate backups too.