I don't think that being either left-handed or right-handed is necessarily an 'all or nothing' thing. For example, I write left-handed and, when playing cricket, I bowl left-handed but I bat right-handed.
However I insert my right arm first when donning my coat.
Snap, gg. Always right arm first and i am right handed. Right footed too - left leg was for balance only when i played football - and it's always right leg first when putting pants on.
I'm a left-handed mouse user, GG. The mouse I'm using at the moment has 'forward' and 'back' buttons on its left hand side, meaning that I have to take care not to knock them and end up looking at the previous web page on my screen!
In days gone by we were forced to write with the right hand at school. Don t remember it being a problem. Eat with left and use scissors. Mouse onthe right and coat.