How to add a time format

I would like to use a default theme. Could you tell me how to add time (23:59)? Or possibly you could rewrite it and upload somewhere, then I hope I will figure out how to rewrite it in other themes. I know that static generators aren’t suitable for writing a large number of articles, but sometimes I could post 2 a day. Or I could make a temporary blog, for one month let’s say, where I would utilize even seconds. Thank you!

I tried this even before posting this question, but it rewrote time of each article, when posting a new article. I tried it with a local host.