This helps add interest to the flow of the written words and avoid cliche patterns that sound inauthentic. Once you find a solid verse melody you can just use it thru the entire verse depending on the song Give Your Lyrics A Natural Flow If you are squeezing a lot of syllables into your bars you are going to need to learn how to transition between the bars to make everything sound coherent.
What you write in the song summary is going to be a giant brain dump of your ideas. And to truly master chorus writing you can check out my how to write rap songs course where I bring you into my studio for over 2 hours and show you step by step how I create songs from scratch.
All your ideas into one giant clump of non-rhymes and non-structure. If you want your lyrics to naturally flow better between every 4 bars, use rhyme words to transition to the next bar.
Just start jotting things down into a big paragraph. Don't be discouraged if you trip up on your words.