how odo i connect it to power overnight

In the same way you connect it to power during the day.

If you don't want to be disturbed overnight, enable Airplane mode on your device, as per these instructions:--> Use Airplane Mode on your iPhone, iPad, iPod touch, and Apple Watch - Apple Support

Regards

Giulio

You do the same thing you always do when you charge your phone. Connect your phone to the charging cable and then connect the cable to the power block and plug that into a wall outlet, then let it charge overnight. You can’t overcharge a phone battery.

No worries about that, Sochi345 :)

Your iPhone automatically stops charging when the battery level reaches 100%. I use that practice since I bought my first iPhone in 2009 (model 3g) and all my iPhones batteries have had an average life of 3-3.5 years, with no issues.

I suggest that you take a look at this useful user tip too:--> When to charge your iPhone or iPad - Apple Community

Regards

Giulio