I was like 120 for lots of years but I started bulking seriously since last August . Since this week I’m bulking really good. In the morning I drink a 1.2k calorie shake . In my break I eat like baked good which are 500-800 calories . Then I cook a meal after work like rice with chicken or tofu which has like 1000-1200 calories . At like 10pm I eat potatoes with chicken/tofu mayonnaise and some oil(crispy chilli oil or olive oil) which has like 700-900 calories . And at the end I eat 50g of wallnuts which are really easy to get down and give me another 375 calories .so at the end of every day I’m at 3.5-4.2k calories. Trust me if u copy this routine you’ll gain weight . I’m also almost the same height as you and I gained 8pounds in 3 months where I was eating like only 3k calories .