18 y/o f at a loss

hi. i don’t know where else to go or who to ask, so any advice is appreciated.
i am 18. i live between my narcissistic mother’s house and my two married friends. i have physical & mental health problems that have debilitated me for years, more and more as time goes by.
i have no car or transportation (i only have the friends i live w/ and my family— none of whom could help me get to or from work)
i have about 2-400$ income a month (i do online SW) but obviously that isn’t really anything. i use cannabis medicinally and spend <$200 a month on it. i can barely afford food and necessities, especially considering i pay about $100-200 in bills a month with my friends.

whenever i ask my mother for help i am made to feel greedy, ungrateful, and unwelcome.
i need a physical job, i need to support myself. i cannot work in food service— i lose my mind. i don’t know what to do anymore. i’m about at my wits end as i have been more than a handful of times in my life but this time i dont know if i can take it. i sleep on the floor or a couch. i am dependent on my mother, but get called a ******* idiot when i say that to her out loud. i need help and i couldnt even get SSI because they denied me. the food stamp office never called me back for a phone interview. my mom also might have cancer, so even if i needed more help im **** out of luck.
i cant walk 2 miles a day to stand for hours at a time. my body wont let me do it. but i have no options. i dont want to fall off the deep end

but yeah idk i just need advice. i dont know what to do anymore. im tired of being a failure and a pest. im tired of being poor and depressed. i just want to feel safe and happy and fulfilled. i dont even know where to start :/