**Karrychen 50pcs Water Test Strips 6in1 pH Nitrite Alkalinity Chlorine Hardness Test Paper https://www.amazon.es/dp/B08LDH7RWS/ref=cm_sw_r_apan_i_J4HBCF16S74WB1Z0W69G. There are many variations of this which are cheap and expensive. This is around average and will give a total overview of your water quality without a laboratory test
https://www.amazon.com/ABCwaters-48k-56sxt-fm-Softener-Filter-System/dp/B004LYGBWM/
carbon filter is optional