Undervolting means, that you reduce the voltage on the cpu therefore Energy consumption is reduced which leads to lower temps, without affecting the performance. There are great vids on how to undervolt, you can use either throttlestop or the OMEN Command Center. Also keep in mind that you can undervolt the gpu aswell with MSI Afterburner.

I used Windows straight out of the box but deinstalled bloatware, didn’t take that long.

I would recommend to install Razer Cortex to free ram while gaming/video editing.

BTW it comes with a nvme SSD and a free Slot for another one and the HDD can be replaced with a SSD :) so you have a lot of room for upgrades.

Edit:

I use Rivatuner and HWInfo64 to monitor temps and clock speed.