There is a drain plug on the bottom of the sump, undo that and the
oil will gush from there. You will need a key to undo it, most Pugs
are 8mm square.

Catch the old oil in a drain tray then transfer it into the container
your new oil came in once you have put that in and dispose of the old
oil in the proper place. Your local council tip will have a waste oil
disposal point -  do NOT pour it down the drains.

Not unless you had the engine running! Most of the oil settles in the
sump, a little is left in the filter though so be careful when you
take it off.

I always seem to make a mess so have a suply of old rags handy.