I weight 165 pounds. My high school son who weights a whopping 85 pounds stood on the roof with no problems. He's away and I need to stand on the roof today. The roof is for the sole purpose of covering a bay window, so I don't know if it is designed to handle a heavy load.
I wouldn't try it. If you know where the beams and stand on them you may be ok but you're taking a risk.
It would be nice if you knew the roof had 2x4 rafters....if it does you are ok.......but do be careful........not much room for mistakes........use a ladder if you can........don't know if you are talking deck or 1 story or 2 story....below you.....the roof should hold...........that's really not a concern....it's footing....good luck
