How can I put on weight all overk? I'm tired of being underweight, please help

Resistance exercise. Lifting weights will add lean body mass. However, it takes time and concerted effort to build lean body mass. Simply eating more calories than you burn will add fat which is not advisable.
Strength training. Have you tried resistance or strength training like yoga or lifting weights? Can you join a gym or the y and get help with an exercise program designed for you? Are you eating enough grains, protein and oils for your age, activity level and sex? Go to choosemyplate.Gov and see what types of foods and activity are recommended for someone like you.