Hi! Yes, you can combined Nepal and Bhutan trip. The suitable route would be first exploring Kathmandu and getting around UNESCO world heritage site. You can keep 7-10 days. In this time, you can als (Read More)o Trek to the Himalayas. I would recommend you to check Ghorepani Poonhill Trek, Annapurna Base Camp, Mardi Himal Trek in Annapurna region of Nepal. Lastly, you can take a flight from Kathmandu Airport to Paro Airport. Then start the Bhutan tour. "Text Hidden"
There are three routes to go from Gorakhpur to Kathmandu and the most preferred route would be to cross the border via National Highway 24, switch to Mahindra Highway in Ramgram, Madan Ashrit Highway (Read More) in Narayangarh, then the Prithvi Highway and finally on the Tribhuvan Highway.