Start with the easiest possible solutions first! Do you have access to an Owner's Manual?
For your dome light, check the switch (three positions, middle is off, one side turns it constantly on, other side turns on only if a door is open or cracked open. These positions work without a key.
If this doesn't work, check the bulb itself. You need to take out the bulb and put it into a socket that you know works (in another car, on another place in your car?). Replace if broken.
AND: The fuse for the dome light on the 2000 Camry is #14 in the long fuse box in the engine compartment.
Dashboard: first, check that your dashboard dimmer is turned up. It's unlikely that all bulbs are out, since there are at least four for the panel and a bunch of bulbs for the many idiot lights that show up when you first turn on the key. Do this at night. The dimmer is to the left of the steering column and is a round knob. Don't be ashamed if this solves the problem, and remember it for a driving test, something they ask in California. However, if this fails, read on.
Do you have an owner's manual? There is a THIRD fuse array behind the COIN BOX by the driver's left knee. You need to be patient, mechanically inclined or have a mechanic/good friend help.
FIRST, note your radio settings. You'll need to reset these later.
SECOND, disconnect your battery connections (both) and then wait 90 seconds or more. This is so that your AIRBAGS DON'T DEPLOY, which could kill or maim you.
If you don't want to disconnect the battery, etc., just be really careful around the airbag (it's in the middle of your steering wheel) or other places where there are airbags.
In my 2000 Camry LE manual, page 256, it lists an Instrument Panel fuse array for fuse #s 20-44 behind the coin box (yes!) just to the left of the steering column. Open the box and remove it (you have to pry and pull—take a careful look). You'll see fuses behind the box, and you'll find a fuse diagram on the coin box's back side.
The Toyota Owner's manual tells you what fuses are for what—but it doesn't specify which fuses actually control the Dashboard (called Instrument Cluster) LIGHTS themselves, only gauges and meters and that dimmer (fuse 34). Using needle nose pliers and with the help of a light, carefully remove the one fuse at a time and test it with a volt ohmmeter. It might look good but might not test as good. If it's good, put it back in carefully and firmly, and go on to the next possible fuse.
My wife and I think the relevant fuses might be #22, 26, 32, and/or 34. I own the Shop Manual for this model and it isn't helpful, because what mechanic or owner needs help changing a bulb?
Good luck. I hope it's simple.
Source: Toyota Camry 2000 Owner's Manual, 1999; 2000 Toyota Repair Manual Pub. #RM742U2