It is Chinese so there is little information about how to connect it. It does not limit the charging current so an additional charger circuit is needed.
I think its 2.5V over-discharge voltage detection is too low, my Lithium battery manufacturer says 3.0V to avoid damage.
Many other BMS circuits show how to connect batteries. Learn how to speak Chinese and phone the maker of this one how to do it.
Oh, it is so cheap that the maker is unknown.