I have a 2000 Honda Civic, and I've been having some issues with it. It is very tough to shift into first, and sometimes when I shift into reverse I can hear the gears grinding and the car lurches a little, even when the car is not moving forward even a little. Another problem is that when the clutch is not pushed in, and I'm just stopped, I can hear a noise that just sounds like a crappy old fan or something, kinda just a buzzing. But when I push in the clutch it goes away. I think it might be the transmission or clutch fluid, or a bad part in the transmission but honestly I don't know much about cars. What is wrong with it?
It sounds like possibly a worn out clutch.
On vehicles with with self-adjusting hydraulic mechanisms (which I think the 2000 Civic has) as the clutch wears out the mechanism will 'tighten up' so that there is less travel as you press the pedal, up to a point where the clutch does not fully disengage and would exhibit the symptoms that you have mentioned.
This is the opposite to vehicles with traditional cable mechanisms which would experience slipping of a worn clutch unless a manual adjustment is made. The hydraulic mechanisms avoid this slipping.
Clutches disengage when you press the foot pedal; the energy of your foot moving is transmitted to the clutch either through a mechanical mechanism, or a hydraulic connection. Difficulty in engaging gears can result from the clutch's failure to disengage. This can be caused by misadjustment of the mechanical mechanism, or a leaky or otherwise faulty hydraulic connection.