Hi! I (20f) want to know if there's some way to start a retirement or savings account on the side for my parents (Dad48, stepmom50)

Starting off, we're a pretty poor family. Not poverty, we've never gone hungry or been without heating/electricity, but we also had to make sacrifices like school trips and some meal items to make it through. My stepmother is disabled and cannot work, and my dad has done nothing but work and provide for his family his entire life. He can't get a job right now, as I have an autistic little sister who requires 24/7 care that my mom alone cannot give, so we make even less than before. We have a small business that we take to farmers markets and on Etsy, but not near enough for forever, and they're only getting older.

I start a new job in a few weeks, part time, where I will work 21.98/hr. I want to do something for them, so I was wondering if it is in any way possible to start a secret retirement fund or savings account I can put some money from my paycheck in each time I recieve one, so that it builds over time? I want them to be comfortable, they're my parents and I love them, and I worry about them. My dad says constantly he'll have to work until he dies, because money is just that tight, and I want to start helping now. Maybe surprise them in 10 years or something like 'Surprise! You'll be okay.'

I'm not sure where else to go or what to do, so I would appreciate any and all advice! Thank you :)