Pilot light on my rheem water heater goes out frequently, model # 22v50f1,about 4-5 years old

SOURCE: rheem water heater pilot light goes out

You have no pilot. Power Venter units use either a sparker or a hot surface igniter. Therefore no pilot.
This is easy, call Rheem Tech support and they can walk you through testing.
Problem is you may have to pull controller which will require draining tank as t-stat is an immersion type.

SOURCE: I have a Rheem 50 gal. natural gas water heater

The most common reason a pilot light will not stay lit is a bad thermocouple. How old is the water heater? If the pilot light will light, but then go out when you release the safety button, that is a sure sign the thermocouple is bad. You can buy a replacement thermocouple at your local home improvement store. There is a small chance that the control valve has gone bad, but that is highly unlikely.

SOURCE: I have a Rheem glas fury model 22-40 gas water - leaking

once they leak it's time for a new water heater. ther is no way to repair a tank leak

SOURCE: dripping from drain spout

If you are refering to the "Dripping coming from the preasure tempature valve,Then just turn off the valve where the water goes into the heater and open the P/T valve with a bucket below it draining only emought water to get below the level where it reaches.     Normally the drain valves are plastic with a Male hosebib attached.  Attach a  garden hose to the rain and run it out to a point lower that the vaslve in order for gravity to drain the tank.The valve opens counter clock wise. If the valve is stuck or does not drain,and you have a foor drain handy,remove the whole valve and replace it with a boiler drain valve.  If The tank is located below the drain level then you will have to either pump or carry the drain water to the higher level.     Replace the P/T valve  and reinstall the associated associated piping. I would use tefelon tape on the P/T pipe theads.    You may have to open a hot water faucet in order for the air to replace the water in the tank ,in order to drain. 

SOURCE: No Hot Water in morning

Remove the cover then the access cover, then you can see inside,
the pilot light is probably out.

If out turn the gas off, then get a long match, grill lighter,or piece of paper ready to light, you should be able to see the little thin
gas line that runs inside the tank and see where it connects to,that is where you need to light, now that you see where to light, turn gas knob to pilot, and press down and at the same time light the pilot.
( blow into the pilot area before putting match inside to make sure no gas has built up inside) Hold down the knob for a minute then release, if pilot goes out try again and hold down longer, if you hold it for 3mins and it does not stay lite, the thermocouple is bad and you will have to replace it.