English speaking drivng instructor

Don't you know anyone who will let you take you take their LH car out for a spin.

It takes something like a month, possibly less, to get used to the fact that you use your right hand to change gear and apply/release the hand brake. Then you will wonder why you found it so difficult to start with.

Why not take up the offer but confine it to a Sunday in an empty car park - supermarket or wherever - so that at least you become familiar with driving a LHD car.
I suspect that you are seeing much more of a problem than there really is and that, once you get comfortable with driving a LHD car, doing so on the open road will be easier.
The reality is that many people switch from driving LHD to RHD and from driving in UK to on the continent as a regular routine without any problem.
Good luck.

You are right to be nervous of roundabouts, they don't know how to use them here. Just get out there and do it. As one person said, you will soon wonder what the fuss was about.

Apart from some wild fumbling with your left hand hand while trying to change gear, it's actually pretty straightforward. And remember which side to drive on. My first trip to Europe (from the UK), I drove off the ferry and immediately went the wrong way around the roundabout.

The most irritating thing is actually why European cars have the turn signal on the other side to the windscreen wipers like in Japanese cars. You always look like an idiot when carefully indicating only to switch your wipers on.

It's not you mike1300GT who doesn't know how to use roundabout its Belgians road users in general. Some think priority adroit applies most don't use indicators, all seem to go round in any lane.
My suggestions are drive on a Sunday but be aware People who drive here as a rule don't seem to leave a reasonable stopping distance so pay attention three or four cars up.
Once you are in your lane go for it don't hesitate who who hesitates crashes here. Ignore all the horn blasting if you say stop for pedestrians. Also a quick course in reading road signs as in how they sign junctions is useful.
Maybe try driving out of town for a while till confident then build up on bigger roads.

I know how to use a roundabout, it's the local rabble that don't. One of my favorites has two lanes approaching and there is always a queue in the right lane to turn left?! Argh!