Osaka - Kanagawa - Tokyo

Hi, i'm going to tokyo from osaka in 12 march 2024.

I want to visit matsuda cherry blossom festival & hakone before ariving to tokyo. In kanagawa, i think i will need to buy JR Tokyo wide pass, because im planning to go to rural kanto region on my itinerary for 3 days.. but i heard it can only bought in tokyo / picked up in tokyo if i buy it online... It said, that to come to matsuda cherry blossom festival, i need to go there from odawara station (if i go from osaka).

The question is :
1) can i buy the JR tokyo wide pass in odawara station ?
2) if i buy JR tokyo wide pass online, can i pick the jr tokyo wide pass in / around odawara station ?
3) if both number 1 & 2 can't, where i can buy it in my way from osaka to matsuda cherry blossom festival ? and can i start using it immediately from odawara station ?