Hello, I think both methods are usefull and it might be good combining them. I have a 3 years old child, and as I have watched her learning our language (spanish) I have noticed that it is more natural and fluid for her trying to say what she wants to in her own way, specially what it comes to vocabulary or tenses. For example, she often refers to some things by definding them instead of use the name of the object. In the other hand, when we learn a foreign language as an adult it is good to memorize some gramatical structures and expressions so then we can use them when we speak. But, for doing this, I think it is really healpfull to practice with a native speaker and practice listening.

Hi! I think memorising phrases is a great tool to build confidence quickly, especially if you're a beginner and still learning grammar. Now that I'm a more independent speaker, I like to learn nearly every word in the context of a phrase that I might actually say in real life. It helps me remember it and feel confident using it, but I don't memorise it, as such.