Retirement tax questions

It starts right with box 2.  TurboTax requests federal taxes withheld.  W-2 (actually box 2a) reports taxable amount of wages reported in box 1.  Box 3 in TurboTax requests Social Security Wages.  W-2 indicates Capital Gains included in box 2a.  W-2 box 4 contains federal taxes withheld.  All subsequent boxes continue to not correspond.