Pub 590B addresses this and details the ordering rules:

https://www.irs.gov/publications/p590b#en_US_2022_publink100089915

I love that we're halfway through Feb already and the 2023 pub hasn't been finalized yet.  I find the PDFs easier to read/follow (especially if you have to use one of the worksheets) so it might be easier to read here:

https://www.irs.gov/pub/irs-pdf/p590b.pdf

Jump to Roth IRAs starting on page 31.

Or if you can tolerate the watermark on every page you can read the 2023 draft here:

https://www.irs.gov/pub/irs-dft/p590b--dft.pdf

"How much should it be?"

I didn't see the taxpayer's age.

"Roth was opened in 2021"

And it seems, unless there is another Roth account somewhere that was opened earlier, there is/are 5-year rules that weren't met, either (age of account, timeframe of basis contributions).

"I'm stumped on the penalty for early withdrawal."

I like to list the actions according to the timeline sequence. That helps identify penalties vs taxable actions.

Only one Roth - opened in 2021. He is in his early 30s. (sorry, that was an important detail).

That Basis of anything that he contributed directly to the Roth (not converted) is penalty free.  Everything else has a 10% penalty.

Contributions were $450 in 2021, and $600 each for 2022 and 2023.

Thank you all so very much.