As far as I know you can not contribute directly to your 401K, but ask your payroll department. Money put into a 401K are deducted from your paycheck by your company, and put into your 401K. You can up the percentage from 7%. Ask your payroll department what is the maximum percentage you can contribute. You can contribute a maximum of $22,500 ($30,000 if over 50) from your paycheck if your employer allows it.
You can also open an IRA for 2022 taxes up to April 15, but you can only contribute $6,000 ($7,000 if over age 50). If you are probably in the 22% tax bracket, so contributing $6,000 would reduce your federal taxes by $1,320. I don't think there is anything you can do to totally eliminate paying federal taxes.
Adding a large amount in 4B on a W4 will reduce or eliminate taxes being taken out of your paycheck, but you will then probably owe a huge amount to the federal government when you file your taxes. Also if you owe too much to the federal government, you will have to pay a penalty for underpayment. I suggest you leave 4b empty for a year, and then see what you owe or get back on that years taxes. If you get a large refund on that years taxes, then put that dollar amount on line 4b for the next year. Then if nothing changes on your taxes, you will come out not getting a refund, or owing.
