G'day, Shaun, from a couple of degrees South of you, and welcome to the Forums.
You have an interesting choice of starter lenses with your 200D. IMHO, the 18-55 kit zoom is generally under-rated (I sold mine when I bought the DA*16-50, but only because I couldn't justify 2 lenses occupying the same range of focal lengths) and there are plenty of photos here to back up that view. I don't have direct experience of the Sigma 30/1.4, but there's a fair amount of respect here, from those who do.
It probably won't be long before you have a hankering for a longer or wider view, so keep an eye on the Forum Marketplace when that day comes (and check out the meaning of the acronym LBA while you're at it!). In the meantime, keep working at your technique, and don't be shy in asking for opinion or help - there's lots of both to be had here.