What happened to the characters that you could just load into the game and start playing. I have played all these games and every one of them had characters that you could just load and adjust their stats. Please help.

I remember every game having pregenerated characters too but don't think I could alter their stats. Did you check if there are pregenerated savegames ?

In the Gold Box games (except Unlimited Adventures), if a character's XP total is exactly the same as that of a newly created character, you can modify the character's stats. This would logically hold true for pre-generated characters if they start with the same amount of XP.

(It also holds true if you manage to get the character's XP to land on the right value after dual-classing or being level drained, and I've read that, apparently, In PoR, it can even be used on a monster NPC who starts with 0 XP. Said monster's stat limits might be outside the normal range, but note that stats above 25 might behave like average stats (as I determined this with a third gender ("COPPER" gender) character.)

It would help if you mentioned the game, that you're trying to play. Forgotten Realms is a scenario, in which several games take place. Some of those actually do have quick start parties. Although not every quick start party's member's stats can be edited. In some games you need to create new characters, if you don't like the ones that come with the game.

Been a while since this was posted, but: most of the pregenerated parties are in the games as saved game A--you can load that game and start playing. I believe Secret of the Silver Blades did not have this one.

In general these are the same as any party you can create, but the Pools of Darkness pregen party actually had dual-class characters already set up with their old class level reached, whereas otherwise you would have to create a character, dual them, and start from level 1.