when you find that when you acelerate you hear the engine noise but cant feel the increase in speed means that clutch plate is worn and is slipping.
Clutch will slip, chatter, smell, or otherwise not function as it should.
You need a new clutch
If the revs decrease as the speed decreases (in 3rd & uphill) then its not slipping, you don't need a new clutch, but if you are in any gear and the revs are increasing while the speed is decreasing, then the clutch is slipping.
you cannot adjust you need new clutch.
Most likely it is the slave cylinder on the transmission. you need to check clutch cylander for leaks only place it can leak is the clutch cylander or the fluid line
Its a hydraulic operated clutch, so its auto adjusting. No manual adjustment. If the clutch is slipping, you need a new clutch plate.
you dont add clutch fluid. If the clutch is slipping that means that you need to buy a new clutch
You may need a new clutch.
Check your clutch master cylinder and slave cylinder for leaks,if no leaks,then you need a new clutch kit.
Clutch plates are sticking - get your clutch checked you might need a new one
There is no tightening. It is hydraulic and self-adjusting. If you have little or no clutch, you need a new clutch or something is wrong in the hydraulics.
You either need a new transmission or a new clutch.