The pro-rata rule will apply to the conversion you made in 2022 since you had pre-tax and after-tax funds in the traditional IRA. This is calculated on Form 8606 or Worksheet 1-1. Figuring the Taxable Part of Your IRA Distribution. You will see the taxable amount on line 18 of Form 8606.
Please be aware, we cannot see your return therefore we cannot tell you how much will be taxable.
As Opus 17 mentioned you should move the pre-tax funds out of the traditional IRA and into the 403B (before the end of December 2023) to avoid this issue in 2023.
@LLC3
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