Continuously means non-stop, where constantly means again and again with breaks in between something being done. That’s how I would use either.

It's a bit of a tricky question actually now that I think about it. We use continuously when we want to say that something is happening without any break or pause. "He was working continuously for 10 hours." = "He was working for 10 hours without a break." We use constantly when we want to say that it is happening very often or all of the time. "The neighbours are constantly playing very loud music."

Continuously.- when u r doing any activity without any fail or gap ....let's say you are speaking English from an hour without any phase Where as constantly means - you speak English for an hour everyday for a month .