Social security tax is fixed at 6.2% and Medicare is fixed at 1.45%, there is nothing you can do about it and nothing on your W-4 can change that. If the amounts are more than 6.2% and 1.45%, check with your employer.
Note that Social Security tax is only charged on the first $168,800 of your income. If your salary is higher than that, then once you have been paid that much, the employer will stop collecting FICA for the rest of that year. Medicare keeps going. See this blog post.
For 2023, the maximum income subject to Social Security tax is $160,200, which means the maximum tax for the year is $9,932.40. The $168,800 maximum is for 2024.
If your income is over $200,000 there is an additional Medicare tax of 0.9% on the amount over $200,000. That amount is the same every year.
Social Security and Medicare taxes are referred to as FICA.