Hi @Witti0 I hope you are well!
You can list to attract monthly rentals only.
You'd need to change your minimum nights stay from whatever it is currently to 28/30 night minumum and then perhaps add a discount to encourage those longer bookings.
You'd be excluding a large section of guests who travel, so might limit your bookings- but I don't know your area so this may work fine for you!
You're new to the platform, so I would say it would be sensible to take much shorter bookings to cut your teeth on, and help iron out any hosting creases- much better to do this with guests who visit for a shorter amount of time than have problems/issues with longer term guests who will always make more use of your home/facilities.
Paul 🙂