How to back up Apple Watch data before re-pairing

During a bout of housework, I must have knocked the button, as my Watch says ‘Too many attempts at Password’ it seems that my only option is to Re-set and re-pair the watch, which seems to mean erasing everything on it. That means I lose months of Activity data and trends.

(1) It is currently on my iPhone but will it be lost from there too when I erase and reset?

(2) How can I back up the data from my iPhone to avoid losing it all? I’m in the process of downloading Catalina in the hopes that then my iPhone will appear on my MacBook when I connect the two, in a way they don’t at present.