at this height weight shoud be between 65 to 75 kg.so your wt is boarder line.to increase your wt do folloing things.
1,take diet rich in protein, add pulses daily in your meal.
2,take high fat milk,about 500 ml to 750 ml.
3,take protein powder daily
4 add khajur,gud in your diet
like pulses about 100 gm keep in the water overnight and take this in the morning as such without cooking,for making it tasty you can add solt in it.
6,take fresh fruits,juices,green vegetables and salads daily.
7,for suplimentation you take multivitamin
, b complex tablets.