You will soon get used to it.
I find that my saloon soon mists up the rear window this weather and leaving the quarterlight open while keeping the heater on tends to clear this up.
Leave plenty of room up to the car in front. The brakes WILL stop if you do an emergency stop but they heat up and fade far more quickly than modern brakes so it's much better if you use engine braking (going down the gears rather than just relying on the brakes).
Also, because there is no synchro on bottom gear you might find that when you select the gear, it might crunch (even when stationary). To get over this, select 2nd gear beforehand and then forward into bottom gear. This soon becomes second nature (no pun intended) and I have become so used to it now that I do it when coming up to junctions/traffic lights in modern cars.
I remember when I first drove a Minor and apart from the noise, brakes and first gear, the suspension 'wafted' a lot when going over bumps. If you encounter speed humps or bumps in the road then go over them slowly as the suspension is a bit more basic that it's modern equivilant!!
Above all, ENJOY!!! I can guarantee you will have a huge grin on your face.
p.s. if the engine is set up correctly then you should be able to get about 220 miles or so out of a full tank of fuel.