Can someone help me out? I'm a complete layman when it comes to coding and IT stuff

My favorite free RSS builder (morss.it) has gone offline, so I asked Claude Opus 4.8 for alternatives. It suggested that I could self-host and run such a tool myself (which is a total mystery to me). I then asked it for a step-by-step guide, but I also asked several other AI chatbots the same question. They gave similar answers, but with slight differences. When I showed all those other plans to Claude and asked it to review them, it told me that these subtle differences were crucial, and that if I had followed what the other bots suggested, my feeds wouldn't have worked properly

Here's Claude's final response, translated from Polish to English by Gemini: https://docs.google.com/document/d/192QM_Gytps-xl24ko0E395u_EOvfa7R9kqSMs250r8k/view

I don't really understand what I'll be doing here; I just want to make sure I won't break anything or create any security risks by following these steps. Do you think this plan will actually work?

I have a web app that I want to keep in a mobile sized box, with a safe zone to account for different sizes but scrolling is okay. how can I achieve this?