I winterized my building on a golf range and drained all water out of supply lines feeding building from my water tank and well. I opened valve at water tank and left open until water flow stopped with sink and supply values in building open, this was done while well was turned off, well is approx 100ft deep. My question is what steps or procedure is to fill tank and get water back to normal. I have done nothing yet this season. I understand that there needs to be pressure in tank. The tank is one year old with a bladder.

Close water heater drain valve.
Open a hot and a cold faucet some where.
Turn on pump.
Close cold faucet when water begins to flow.
Close hot faucet when water begins to flow.
Turn on water heater. (Do not turn on until water flows out of faucet)
Open all faucets briefly and flush all toilets to let air trapped in lines escape.

Great advice. I will only add that, concerning the pressure tank, the pump will build pressure so don't think about adding air.

You might want to do this while the pressure tank is empty anyway. Check the pressure at the top of the tank with a tire pressure gauge. It should be about 2# below the pressure point where the pump cuts on once it begins cycling normally after you have turned on the pump.

Also note that you do not fill the pressure tank. It will only take on a very small amount of water, the rest will be air. On many pressure tanks the bladder is about 2/3 to 3/4 the way down the tank, so even after the air under the bladder dissipates, the tank should still never be fuller than 1/4 to 1/3 full of water. If the water level gets higher than that, you have a bad tank.