Buying a new iPhone

[SCantiGOP]

I was very fortunate to have a new iPhone every 2 years, fully set up and supported by my company IT department, but I retired three years ago and now have to buy a new one.
If anyone cares to offer any advice, it would be appreciated.

1- Which phone should I buy, and where is the best place to get it?
2- Will they fully set up the new phone and transfer all of my date, photos, notes, etc to the new phone?
3- Will the new phone then be synced to my computer and iPad as it is now?
4- And finally, is my Apple ID all I need for this process? There is not a separate iCloud ID?

Thanks if anyone wants to weigh in.