If you want an informed opinion, you have to describe your playstyle. Some questions to answer:
How good are your poking/footsie skills?
Do you tend to choke on defense without a reliable invincible reversal?
Are you willing to learn long combos, or would you prefer to keep it short and sweet (and quite possibly less safe and/or less damaging)?
Do you tend to do better getting in people’s faces or hanging back and letting them come to you? In which situation would you feel more confident against a player who’s more skilled than you are?
What characters have you played previously? Which of those characters did you do best (win the most) with?
Have you ever entered a tournament before? What games did you play? How well did you do? Do you even care about getting to the level where you can compete with tournament-level players? (not talking Daigo/Justin level, more like whoever are the top guns in your region’s fighting game scene)
It’s just like Starcade said, all you’re going to get is arbitrary opinion unless you provide more substantial information.
Some VERY general comments based on your list:
Gen is a very difficult character to get into (not just execution, but in terms of how mediocre most of his tools are even in skilled hands), and so I would really advise against trying to play him seriously at the beginner level.
Fei has a lower execution barrier than Gen, but faces a lot of the same strategic hurdles. Unless you’re really dead set on learning Fei’s quirks, there are better picks if you just want to rush people down.
Cody is probably the easiest of the characters you listed to play at the beginner level, but he’s not a free pass. He has a very easy c. LP, c. MP link that makes it easy to whip up Hurricane Upper/Ruffian Kick combos, he has a lot of good normals, and he can harass slow non-fireball characters with rocks, but he’s not going to win sustained fireball wars, he moves surprisingly slowly, and his reversals aren’t all that great. Many matchups involving Cody look to be a matter of time until they get on top of you, and then you have to have very strong fundamental defense (blocking, throw teching, smart backdash) to get back to your better range. Playing Cody will still require a strong knowledge of proper spacing so that you don’t waste a lot of time and life trying to kick somebody off your corpse, or having to get back in on a strong zoner like Sagat to reclaim the life lead.
Guy has less in the way of cheesy links than Cody but he still looks to be pretty solid in a different way. Will probably require at least as much execution skill as Fei Long to go far, however, and you absolutely cannot be jump-happy with Guy since his jump is so floaty and his elbow drop isn’t a cure-all. He also can’t run around randomly the same way Fuerte can, he requires more deliberate spacing to win at footsies and get into optimal attack range.
That’s all I can really comment on based on no information about your playstyle/what you want out of the game.