I actually intended to spend all my 14 days in Tokyo to just slowly going around to take in the daily Japanese life. I have booked an AirBNB room near Yazaike Station, Adachi from the 16 March - 23 March. I am would like to maybe visit a ryokan and onsen. Can I find that in Tokyo? On week 2, I would also like to visit Nagano, Niigata, Kesennuma, Iwate. Would I be able to fit them all in?
- Ryokan and onsen
I don't think there was an onsen ryokan (meaning ryokan with onsen) in Tokyo. However there are some ryokans with great atmosphere, many of them in Asakusa: https://hubjapan.io/articles/10-best-ryokans-in-tokyo-for-a-traditional-japanese-stay
In terms of onsen, there are some day spas in Tokyo. There are many Sento along with onsen. Sentos are public bath but do not use spring water, just a hot tub. https://hubjapan.io/articles/10-best-onsen-and-sento-in-tokyo-for-your-relaxing-time
If you can schedule one night away from Tokyo, take a trip to Hakone Onsen, Nikko (Kinugawa Onsen), or Ikaho Onsen. There are lots of great ryokans with delicious local cuisine and relaxing onsen. At Onsen ryokan, you can basically get into onsen at anytime.
- Visiting Nagano, Niigata, Kesennuma, Iwate
It's different where in each places you want to visit. For example if you want to visit Nagano from north to south, you might need few nights to explore only Nagano. I went to Iwate last March and spent 2 nights there. It was enough to explore Morioka and Hiraizumi for us.