Speaking and writing, in any language, consists of two very different skills. While one can definitely benefit the other, learning each one is something you will need to pursue independently.
When immersed in an environment where a particular language is used, especially as a child, we pick up the speaking aspect naturally. It’s as good as automatic, provided we have people interacting with us to allow the experience to happen. Writing, on the other, hand has to be taught. Without directed instruction, even in an immersive environment, it’s unlikely you will learn how to put language to paper.
For language learners, this is a very important distinction to draw. If you think you can write in a language without being able to speak a decent amount of it first, you’re kidding yourself. You can’t put your thoughts down to paper simply because you can’t formulate them without having the ability to express yourself in speech.
As such, you have to at least speak at the most basic level, before moving on to reading and writing. Remember that when designing your own language learning lesson plan, so that you don’t end up wasting more time than is necessary.
Most language acquisition software do take this into account. That’s why they integrate different mediums such as audio and video, apart from text. Doing so, you can learn in an immersive manner without being forced to read (or write) materials that you can’t comprehend.