Roth 401K

Follow-up to my first question..

My understanding is:

1. If I open a Roth IRA any time in 2023, it's start date is Jan 1, 2023?

2. The 5 Year rule is in play to Jan 1, 2028?

3. If I move more un-taxed money into it from another account at ANY TIME in that 5 years, is that money available tax and penalty free on Jan 2, 2028, or does the 5 Year rule start every time I make a un-taxed contribution? 

4. Or, is that money automatically taxed when it is deposited into the Roth IRA?