You've only been playing for 3 days???? And you think that you should be as quick as everyone else????
Seriously mate, it doesn't matter how long you have been racing in real life, you can't expect to get on LFS and start winning races straight away....especially with using keyboard.
There are people on here that have been playing this game for several years (including myself) and still aren't the quickest out there.
There is one thing you are gonna have to learn very quickly.....and that is that you will never start winning races straight away. It takes a lot of practise and the right setup to become good at this sim. Even when you get your G25 you will still be slow until you get used to how the wheel handles and how LFS performs.
Don't take this the wrong way but you sound like a typical noob who can drive a kart fast in real life and expects to be able to perform the same way in LFS. If you are thinking that way then you are sooooo wrong.
If, after a few months, you are still 2 to 3 seconds slower than everyone else, then come in here and ask the same question you just asked. Then, and only then, will someone have some decent advice for you.
Sorry if I sound harsh, but that's the way it is.