@Happyinheels - I would suggest you look at a whole body session from several programmes and start with the one which appeals to you most. As @FrostyFifi says, Iron is "designed that you do 5 a week with two active rest days, and been designed that you'll hit all the muscle groups each week" - but so are all the otheat.
Some are very focused on lifting heavy, others have a significant cardio element. Some programmes' workouts are of longer duration than others. I always get confused as to which is which, but I always seem to come back to EPIC Heat. We all have our personal favourites, but they are all great.
Regarding weights, 2.5kg is a good starting weight, but I'd also get a 5kg pair. You'll find that you'll outgrow the lighter dumbbells quite quickly, and Caroline doesn't really use kettlebells. I generally have one set for arm work and a heavier one for legs. In time, the heavier
heavier dumbbells become my arm weights and I acquire a new set for legs. Currently using 8 and 10kg but working towards 12kg... (I'm nearly 70 and loving it!)