Returning Member

Contributing to an existing IRA account from own bank account for tax deduction

My wife and I have joining tax return.  My wife has been contributing money to 401(k) from the company where she works, and i’m retired without income. So my question is can I use my own money from bank account to contribute to the existing IRA account? Can my wife also contribute money from her own bank account and claim tax deduction? Is the money contributing from the bank account considered after tax which is not taxible when widthdraw?