You can go there by Bus or by driving yourself. You have to reach Chopta, from there you have to walk till Tungnath, 30-40 mins trek depending upon your speed. Bus you'll get from Rishikesh because i don't think there is direct bus from Delhi. I went there with friends by our own car driving. Its a long journey though. We went from Delhi.
Yup by bus or your own convince and there are many beautiful place you can visit like chandrashila trek about 5km, omkar Rameshwar maharaj approx 20km , sari village 20km,dhortal , ukhimat , dugalbuitta.