Hello

After qualifying GATE exam you can apply to any of the following institutes for PhD in Statistics:

BHU (but you will have to give BHU  Research Entrance Test (RET) )

Amity (on the basis of GATE)

Central Universities on the basis of your GATE score and inetrview

Different institutes have different criteria for giving admission in PhD courses after even qualifying GATE. For more details you can click on https://engineering.careers360.com/articles/gate-qualified-multiple-options-for-you