Hello, Luiz!
You may create one main season, let’s say, January 1st, 2020 – December 31st, 2021. And then create two additional seasons for Low and High seasons, setting desired dates range.
This will allow to set standard rate for your main season and set different rates for Low and High seasons. Under Rates tab, make sure your Low and High seasons are placed above the main one, in order to give the higher priority to these seasons while calculating the booking price: https://prnt.sc/sd84le.
Regards,
Andre