Yes you do, even the travel to Ireland from the UK has now been restricted to passport holders only.
No
Probably photographic identity such as a passport or suitable driving licence. Requirements depend on the ferry company.
No.
No but you do need I.D.
No but you will need photographic identity. Check wit the ferry company.
yes you do in order to travel you must have a passport
For a ferrytrip from England to Amsterdam, the Netherlands, a passport is needed. During the trip, the border between the two countries is going to be crossed.
no - it's an internal UK ferry trip
You don't need a passport as such but you will need an identification document with a photograph. Other documents such as a driving licence may be acceptable. This is not for entry to the Channel Island but to identify yourself to the air or sea ferry company transporting you.
If you are talking about Shrewsbury in England, then as both are in England you will not need a passport to travel there.
Strictly speaking, you won't need any ID to get on the ferry from Portsmouth to Guernsey. However, if you are not a British citizen, it might be best to take your passport with you.