Can I use the pass in all transportation?

Hi Eduardo and Marta,

The JR Pass covers all JR lines nationwide, this includes the Shinkansen but also local JR trains, JR buses and the JR Ferry to Miyajima. Other transport, run by other companies, is not included. For example, the Tokyo Metro.

For Cherry Blossom, I would go to Kansai and visit Kyoto, Osaka and Nara. These will likely be in bloom when you visit.

For seat reservations, please see
https://www.jrpass.com/blog/reserving-seats-boarding-the-bullet-train:

Hope this helps,
Daniel

Thanks Daniel -san!
Strongly appreciate your help.

One additional question. If we use the travel from airport Marita to Tokyo and Tokyo to Osaka and return?
What will be most advantageous the single tickets or the 7 days pass?
Thanks and have a nice day
Eduardo and Marta