I'm not "new" to this site, but I don't have a great understanding on how to make a winning team, how to make realistic offers, and how to game plan for the opponent. How would I build my team to make a championship team? How do I scout teams with effectiveness? How I would plan for the future?

Here is where I send new coaches in my league:
https://usflwfl.myfootballnow.com/community/1/3513?page=4#23711

Or you can seek wise counsel and knowledge from the MFN God himself...
https://www.youtube.com/watch?v=bWdfDsLvm9I

Jobu! j/k

https://www.youtube.com/watch?v=bWdfDsLvm9I

when your scouting offenses and defenses for your next game, should you let the computer do it, or should you scout plays that your offense and defense isn't familiar with?

Oh, I'd definitely scout them myself. For me? I take an opponent's defense and try to defuse as much of their highly utilized defensive plays as possible and then when scouting their offense I again look to chip away at and marginalize all their most explosive plays for the most part. I wouldn't leave it to the CPU.

But I have to be honest....sometimes when I'm playing an open team and I lose to them I feel like Desmond from LOST pushing the button every 108 minutes and wondering 'what for....'! lol

JDB has said that you derive more benefit from scouting a play that an opponent actually uses than from trying to improve your knowledge of a play your defense is unfamiliar with (but the opponent uses only occasionally). So, even if you already have 99-percent knowledge of a play, scout it if your opponent is likely to run it. I hope that relates somewhat to your question.

Boom, exactly.

Easy !

Build speed on the edges and deep D. Be sure not to land in a league with Grandadb....but be sure to land in the same division as Punisher....doesn't get more complex than that. (j/k)