Hello and welcome, Dunner!
I'll start right out by saying I'm no pro and there are no doubt others here infinitely more knowledgeable and better players than I am,
but I think how long you stay on any particular lesson is a personal preference.
You may pick up on some quicker than others or you may want to review and repeat certain lessons. That's one of the beauties of this site...
you go at your own pace. There is no pressure to "keep up" with anyone or be done by a certain time.
I would suggest just go with what feels comfortable and HAVE FUN!
Good Luck and enjoy,
Lou