IF South bound on 7th Ave in Manhattan can you make a left hand turn 34th St?

No, you cannot make a left-hand turn from 7th Ave onto 34th St in Manhattan. Southbound on 7th Ave, you can only make a right-hand turn onto 34th St or continue straight.

Making a left-hand turn from 7th Ave onto 34th St is prohibited due to the street configuration and the presence of a pedestrian plaza on 34th St between 6th and 7th Avenues.