Retirement tax questions

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  • If you have a 401(k) with your current employer, ask if the plan accepts rollovers from your IRA account. Try to roll over the old 401(k) money out of your IRA so that you can convert after-tax IRA contributions to your Roth IRA in the future, otherwise, a chunk of your rollover is taxable.  "

I just realized that...after accounting for my earlier IRA, I just went from a refund due to an amount owed. 

Since my first IRA has a combination of 401K and non-deductible $ and the funds have been growing since 2016, how do I specifically roll over my 401K money separate from my non-deductible funds?