Can you change it a little and make it 1-2 sentences?

It's important to stand up for what you believe."
3 examples are:
The first example is "If anybody has anything to say to Raymond, anything to say about his big head, they have to come by me.". The second example is "And I don't play the dozens or believe in standing around with somebody in my face doing a lot of talking.". My third example is "I much rather just knock you down and take my chances even if I am a little girl with skinny arms and a squeaky voice, which is how I got the name Squeaky.".

Standing up for one's beliefs is demonstrated in the actions of characters like Squeaky, who defends Raymond against insults, refuses to engage in verbal taunting, and is willing to physically confront those who challenge her, despite her physical appearance.

Can you do that but put " It's important to stand up for what you believe"

It's important to stand up for what you believe, as showcased by characters such as Squeaky who defends Raymond from insults, refuses to engage in verbal taunting, and is willing to physically confront those who challenge her despite her physical appearance.

To demonstrate the importance of standing up for one's beliefs, here are three examples: First, if anyone wants to criticize Raymond's large head, they will have to deal with me; second, I refuse to engage in insulting banter or tolerate someone confronting me with excessive talking; third, even as a small girl with a high-pitched voice, I would rather physically defend myself than back down, hence my nickname "Squeaky."

It's important to stand up for what you believe, as exemplified by Raymond's determination to defend his friend and himself, his refusal to engage in pointless arguments, and Squeaky's willingness to fight despite her physical appearance.