Can I be fired with cause for refusing to do tasks that exceed my job description/excessive work compared to coworkers?

To preface, I am autistic and often find myself in very difficult life situations. I have also been fired in the past when I was younger for standing up to employers who tried to take advantage of me. Ashamed to say, I have been forced into being a yes man for fear of losing my job. When you are autistic, in my case, most companies feel that they can do without you.

I like my current job alright but I am walked over every day. I know from past experiences that if I were to start advocating for myself the majority of my coworkers would turn a cold shoulder towards me and worst case start a group bullying campaign to force me to quit. Im already tolerated at best, not really liked. I cant afford to lose my job, literally. My boss asks too much of me, can they fire me without cause if I start pushing for equal treatment?

Keep in mind, I am autistic and that matters. They really don’t want me at this place or value me, I fear that I will be fired and ultimately fucked the very second I say no like in the past.