So some perspective;

    * 10,000 years ago, the average atmospheric CO2 was about 280ppm.
    * In 2022, the average atmospheric CO2 was about 420ppm.
    * OPs baseline indoor CO2 is 700-800ppm.
    * For a brief time when cooking, OPs indoor CO2 is 3000ppm

700-3000ppm CO2 would be catastrophic for the climate if it was the average atmospheric level (but fortunately we haven't messed up this bad yet)

But when it comes to the effect on the body, and I am not a medical professional of any kind, but normally exhaled air contains about 4.5 percent CO2 ( or 45,000ppm), so while breathing in air with 3,000ppm or 0.3% CO2 probably isn't optimal for us - our lungs are constantly dealing with much higher concentrations. So nervous shallow-breathing worrying about CO2 levels of your home probably has a similar effect to OPs cooking. ¯\_(ツ)_/¯