I have an idea, that the character can get old.
I am not a moderator, so i think any moderators can make this mode,
it will be very fun i think

That would be tough to program into the engine. Anyway, you would of had to spend over 1000 ingame days to barely get older.

But i will be 700 years old when i get older in the game...

The problem with this is adjusting the age for the NPCs as well. It wouldn't make sense for just the PC to age (and if you ask me, I found that a touch odd in Fable where I'm 65 and my oldest bride still looks like she's in her hot 20's. Err.. not complaining or anything. It's just.. odd).

On top of this, just how quickly does each race age? Some may age quicker, some may age slower.

Next problem, even if you could get a mod to adjust the age of the PC and NPCs based on in-game time, how would you handle death from old age? And then if you managed that, how would you deal with all the NPCs dying?

I admit it would be funny to let all the quest essential PCs get old and die from old age, only to be knocked unconscious instead, and then get back up to die again.

Also, I'm getting this humorous image of decrepit geriatric Dremora with dentures.

By the way, an elf character won't get older