Unit Measurements

I am trying out sketchup for the 1st time. I want to change the measurement unit to mm not inch as I live in the uk.

I found on the page in settings a way to change this but even after i select millimetres the units are still in Inchs.

im using sketchup web free

Please can you help.

You can choose metric units when you start a new file or you can change the units in Model Info.
Screenshot - 2_22_2021 , 2_33_28 PM