Instructions may vary by brand. I am assuming you are not trying to replace the mechanism. Here is advice on adjusting the presser foot as is done for different types of fabric, on a Singer machine:
You might try googling "adjusting the presser foot on a X machine" replacing X with your brand. You well may find YouTube videos addressing this for your brand/model.
Answers & Comments
Instructions may vary by brand. I am assuming you are not trying to replace the mechanism. Here is advice on adjusting the presser foot as is done for different types of fabric, on a Singer machine:
https://theseamanmom.com/change-presser-foot-pressure-sewing-machine
You might try googling "adjusting the presser foot on a X machine" replacing X with your brand. You well may find YouTube videos addressing this for your brand/model.