Ferries to Hokkaido

Hi, Im looking at possible routes via taking a ferry to Hokkaido from Aomori / Hachinohe, to preferably Muroran or Tomakomai.

I have a few questions

1) The Internet booking for Silver Ferry service from Hachinohe to Tomakomai requires a telephone and address. Can I simply put those of my country of residence? I'm assuming that these are used for verification based on my limited Japanese.
https://www.yoyakuinet.silverferry.jp/searoad/

2. What would be the bus to take from JR Hachinohe to Hachinohe Ferry terminal? It doesn't really seem very accessible.

MY plan is to take a overnighter from Aomori to Hachinohe to Tomakomai and travel from Hachinohe to Toya. There is a ferry from Aomori to Muroran but it seems that it is only for afternoons and I'm unwilling to waste daytime on travelling.

The Internet booking for Silver Ferry service from Hachinohe to Tomakomai requires a telephone and address. Can I simply put those of my country of residence?

I doubt so. The internet reservation form seems to be made for Japanese residents only. You can try it, but I suggest to phone.

What would be the bus to take from JR Hachinohe to Hachinohe Ferry terminal?

20 minutes by taxi from Hachinohe Station or 15 minutes by taxi from Hon-Hachinohe Station.

How much would taxi fares cost and are there local bus lines serviing the area? I was thinking of Aomori-Tawadako-Hachinohe and taking the ferry over to Tomakomai-Toya but I'm worried if the ferry would get be out of berths for walk-ins. Ill be there around 12-13 of Sep.

The safer option would probably be to take the ferry from Aomori to Muroran in the afternoon and stop over there but unless there is good scenary along the way it seem like a waste of the day.