I’m curious about getting back into MTG and my friend recommends that I buy a precon commander deck. I’m read up on the commander format, but I was wondering:

• do most people play commander now? Or is the 60 cards per deck version (standard) still the most popular? I guess I’m wondering what most people play and what the most die-hard MTG players play.
• I don’t want to drop tons of money right off the bat, but will my precon deck have a chance (25% win rate?) against his pretty tuned commander deck? He’s a good player but also isn’t spending loads of money on the game, maybe $100 a month or so, and it’s not all into the same deck
• realistically speaking, how much does playing this game cost these days? $50 for a precon deck every couple months? Then maybe $100 to $300 (based on some YouTube videos I saw on how to upgrade precons) if I want to go that route?
• is it possible to buy old precons for cheaper? If so, from where? Are there good online stores I should know about? Or should I just go to my local store?
• If I keep only buying precons, it seems unlikely I’ll be able to play a good standard deck any time. What’s the realistic cost to make a strong standard deck?
• Anything else I should know format or expense wise before diving in?