2020 Acer helios 300, issues?
I have used Acer Predator Helios 300 (2018 version, PH315-51 and also 2019 version, PH315-52), hence I think I can answer them satisfactorily. Let us start with the good news.
There is no modern laptop on which Linux cannot be installed, i.e., yes, you can easily install any Linux distro on this laptop. I have personally installed around 7-8 distros, and all run fine.
And now comes the bad part.
Fan speed - no, I have not yet found any software which would let me control fan speed. Believe me I have spent the first 2 months daily searching for any software which would let me control the fan speed, but all in vain. Hence I would conclude that it is not possible to control fan speed. Believe me, I have tried a lot. A LOT.
Battery life - Battery life is pretty much poor on helios 300 itself (whether on Windows or Linux), due to the power hungry hardware. On windows I get around 3-4 hours and on Ubuntu I get around 2.5 hours of screen time. However, under very low usage, windows can get upto 5 hours, but on Linux it doesn't matter whether the laptop is in idle mode.
Overheating - It does not overheat, but still it is a bit warmer on Ubuntu (Ubuntu - 60 normally and Windows - 50 degrees normally), than on Windows. But undervolting will help to reduce the temps significantly. Check this answer I posted in the past, to successfully undervolt your laptop.
Summary - since you bought a gaming laptop, hence you shouldn't think about the battery life, as it will suck eventually. About heating, not a huge deal. Regarding fan speed, always game on Windows, as games are more optimised on Windows, hence don't worry about fans.
My advice - go for it. In the end, if you don't like it, you can always remove it, without any hassel.
Also I would suggest you to reinstall Windows 10 on your PC (as preinstalled Windows is very bloated). Download the Media Creation Tool from Microsoft's official website. After reinstalling download the softwares like Predator Sense from acer's official website. Don't need to download drivers, as windows will automatically download them for you.
Happy gaming.