It's a built in tap tempo that could be better, unless you like the mouse. In the top header Under Project, click Insert tempo changes. then when you click on the tap tempo button you can keep clicking your tempo, or you can switch and use the space bar after the 1st click.
But you will find other methods that may come up in this topic that will be better in my opinion, such as set beat measure at now time. I can't explain the process now because I have keybindings for all these things.
I missed the word delay, sorry