The Petunia top is written in English only using US terminology.
It is a advanced beginner level, as long as you know basic stitches like treble crochet and clusters, then you should find the pattern simple, there are detailed steps and photos throughout to help guide you.
This pattern is a made to measure design, this means you take your own measurements as directed. This means it can be made for any size and age.
You will need any type of light worsted weight or DKL weight cotton or any other fibre yarn and a 3.5mm crochet hook. I used roughly 600m for the sample size (UK 8).