If you just started learning Persian language, you first need to know some basic rules of the language. If Persian vocabulary is the bricks of the language, then grammar is the mortar that holds those bricks together. There is a common impression that learning Persian grammar is painful, but it is a lot easier than many other languages.
Remember that developing a solid foundation in Persian grammar will not only help you create your own phrases correctly but will also make it easier to improve your communication skills in both spoken and written Persian.
Study all the lessons and incorporate your learning into your speaking and writing.