Hi Dave,
the 2x articles explain very well what makes a kite more beginner friendly especially this one: kitesurfculture.com/blog/32/Do-you-really-use-the-right-kite-shape-for-your-riding-style
It doesn't mean you can't learn with a freestyle kite, it just means that it makes life more difficult, doesn't give you as much wind range, etc. everything is well explained in the articles.
You can also watch this video:
At your body weight, if you only have to have a single kite, it should be a 10m kite.
If you're going to get 2x kites, it should be 9m + 12m.
3x kites = 7m + 9m + 12m
It doesn't matter if you think you got a good deal or you paid very little money for your gear, it's more important that you buy the correct equipment and in good condition. A kite that breaks easily upon impact is probably a kite that was very worn out and was not worth buying in the first place and now probably not worth fixing either.
Also, it's called Lines, not strings.
My advice would be to get a professional lesson during which you can use a more beginner friendly kite. You can then get some good tips on riding and what gear would suit you best.
Christian