Questions regarding programming a trading bot

Background

I have programming experience and I want to try to create an automated trading bot. Don't really care about Strategy atm, will get to that once bot is capable of trading. Have 0 experience in trading in general.

Question

  1. Is it even possible to code this on my local computer? I've read posts on the reddit on stuff like Strategix Trading free trial, but they taut a "Low Code Solution" which I'm not particularly interested in. QuantConnect/Lean is said to be free, but I would like to know how much coding is actually involved, and I don't really understand what they will do that I can't do on my own (once again, no trading background, are they a brokerage? Do I need an account?).
  2. How much storage/processing power is required? I only plan to do small scale (no trading experience so no idea what "small" is. Like 10 stocks?)
  3. What is considered a "good" trading speed? Do people do real time calculations and trade from that?
  4. Do any of these have a processing fee for buying/selling? If yes, is there something like a test share? If not........?
  5. Any "Please don't do this stupid mistake while coding and cost yourself immeasurable pain" advise that you feel necessary? Anything i SHOULD know?

Sorry if these are stupid questions. I tried reading the posts here but I felt that a majority of these type of questions were about trading strategy more than the programming aspect.

Thank you in advance.

Edit 1. Current advise is "Paper Trading" and a lot of "it depends based on strategy"

u/ssd_666 recommeded Part Time Larry (Youtube) for coding and Building Winning Algorithmic Trading Systems (Kevin Davey) which seemed really popular here. Will check it out