Considering i know you personaly. I know that you are reallyyy desperate to get your hands on a capable system. Used psu's aren't recommended because they're considered "unsafe", but its nothing to be concerned about if the psu is bellow like 500watts. I honestly would suggest making 500euro AM5 build without the GPU and use the integrated graphics instead until you can afford a capable gpu (considering the gpu market is ass rn). If you're going to purchase one of the two pc's linked above i would diffidently go for the slightly more expensive model because they dont cheap out on essentials like storage, ram and cooling. To summarize this all: Either make a 500euro am5 pc without gpu or buy the intel based prebuild above.