https://www.amazon.com/dp/B085HNGLZR/ref=cm_sw_r_awdo_211PP9R7SY6EH123AWQP?psc=1# I'm pretty sure this is what I use.
I had that exact same problem! I had used a dongle and that didn't work. the fix was, I bought actual cables, USB-C to DP. plugged in from the laptop to the monitor directly. I get a smooth 4k, 144hz on my monitor that is rated as V-SYNC compatible. I am not sure what your monitor has, but it is Freesync, it might not work with the NVIDIA GPU.
I bought these:
https://www.amazon.com/dp/B08BXPVPPQ?psc=1&ref=ppx_yo2ov_dt_b_product_details
https://www.amazon.com/dp/B09HKL7M2N?ref=ppx_yo2ov_dt_b_product_details&th=1
I think I am currently using this one:
https://www.amazon.com/dp/B09M38CXZ3?psc=1&ref=ppx_yo2ov_dt_b_product_details
This absolutely DID NOT work!
https://www.amazon.com/dp/B085HNGLZR?ref=ppx_yo2ov_dt_b_product_details&th=1
Beware the dongle!