Don't try and enter normal pension contributions or associated Additional Voluntary Contributions (AVCs) made to your employer's pension fund, because you will already have received tax relief through Payasyouearn (PAYE).
For non-deductible contributions to a traditional IRA (where you make too much income to qualify for a deduction), or regular contributions to a Roth IRA, or saving in a taxable account, youpay income tax asyouearn the money, regardless of what you do with it.