I have to install a hepa filter which is 277 volts I need to istall a receptacle and control switch how can I do it while 1 have 3 phase 110/208v supply also I have 3 phase 480volts. How I will have 277 volts single phase line?

You need to check the 480 Volt 3 phase system to see if it is a 4 wire system, which most likely it is. A 4 wire 480 Volt system will have a neutral, and any one phase to neutral will provide the 277 volts your looking for.

If the neutral does not exist, a transformer will be needed

I do need to caution you, that if you have to ask a question like this, your clearly not experienced or knowledgeable about electrical systems, or the trade, and should hire a qualified electrician to install this circuit.

DO NOT, under any circumstances, open the 480 Volt panel while it is energized.

480 Volts takes no prisoners.

Yes sir like the pro said 480 v don't play!! You get shocked by it you will be lucky to survive.. but read the label on the device real carefully does it say 277 v max or just 277v only?