Is there a price line indicator? "Price @ (time)"

I have a “day open” indicator that prints a horizontal line across the chart, reminding me of the day open price.
I need to print another line like this, but there’s obviously only one opening price for the day. It might be called “price at (time)” and it should only stay on the chart for an hour or whatever - not 24.
Does this exist?

Market opening occurs once a day and remains fixed, if that is what you were interested in.

Like any standard indicator, it has certain settings and you can change it for yourself.

I have been a swing trader for quite a long time. I am now planning to become a day trader. Are there some more things that I will have to learn?

You can make changes on the settings as per your convenience. It is exactly like a standard indicator so don’t worry.