My fabia start to make a noise in first, now to months later all the gears make a grinding noise. when i depress the clutch the noise dissapear but when i stsrt to run the grinding noise is terrible

Get it seen to mate sounds like the box could be on its way out.

This sounds as if the box is short of oil and is noisey when the input shaft is turning. Pushing down the clutch stops the gearbox internals from rotating and the noise stops. Probably an oil leak has been taking place over the last few weeks. The drive shaft inner rubber seals can split and leak oil as you drive. As above, get it checked immediately. Good luck!