Just like English or it’s presuccessor, the Latin language system, uses prefix to indentify a word.
肉 means meat and in ancient symbolic characters, it was written like this.
It is not 2 horizontal strokes like the letter moon but should be like this ⺼. However, later on most people mix the 2 up and even in Chinese dictionaries, all words of meat, organs or body parts cone into the moon radical.
On the right hand side, also it is not the letter 市， which is a slash and the whole letter has 5 strokes. It should be like this 巿，with a vertical stroke all the way down with 4 strokes.