Stolen Macbook

Hi, I've just had my macbook pro stolen. It's quite an old machine and running El Capitan. I'm not quite sure what information I have on it but its logged into my icloud. I've read a few articles on what to do but have ended up feeling confused.

I've locked the device using FindMy and have also read i should update my passwords. However, if I update my icloud password will it disable the FindMy, therefore cancel any request?

The machine is switched off and probably extremely low on battery as given the age it doesn't last long without plugging it in.

Could someone advise on what to do?

many thanks