Retirement tax questions

@dmertz thank you for this. I have a question which I may have asked you before but need a little clarification if possible please: in a scenario where my tax return shows a NET income of just $1,000 for a given tax year, what happens if I deposit $6,500 into my Roth IRA despite only making $1,000 in NET income? Will I be forced to withdraw the funds from the account, will the funds be double taxed, both or something else? Thank you for any information on this.