The simple answer is don't drink the water: the heavy metal content (particularly lead) is many times higher than you want.
If you go down the filtering route make sure that your filters are accessible enough that changing them isn't a chore and set reminders so that you always change the filter. It won't be often enough that you'll build up a habit for changing them and you really want safe drinking water.
They're very comfortable to listen to, partly because they don't have much variety. 604 has most of their best songs (imo) Discotraxx, Another Breakfast with You, Playgirl, and Ladybird are all great, slightly sad sounding.
India is not a commonwealth, but is a member of the Commonwealth of Nations. Charles III is the head of the Commonwealth but not the monarch, he is separately the monarch of some (but not all) Commonwealth countries. Most Commonwealth countries are republics.
Australia is both a commonwealth (in name) and a member of the Commonwealth of Nations, but those are two separate kinds of commonwealth.
To summarise: All commonwealths are commonwealths but not all commwealths are the Commonwealth of Nations and not all members of the Commonwealth of Nations are commonwealths (although some are).
Shame Bethesda don't have writers any more