How to set CPU to Performance / Schedule reboot (R4S)

Hello,

First question, how to set CPU Governor to Performance?

I searched and found this, by going to System>Startup>local startup

Then paste this command and save

echo performance > /sys/devices/system/cpu/cpufreq/policy0/scaling_governor

exit 0

Is this command supposed to change all cores to Performance?

Second question, is there a simple schedule reboot package that I can install using LuCI page, System > Software to just reboot the R4S at a certain time like other routers?

Can you describe problems you are facing?
For CPU power - try sysctl kernel.timer_migration=0 | tee -a /etc/sysctl.conf
Utually it is not power itself but powersaving by descheduling system maintenance threads to put CPU idle.
Reboot is almost certainly a mistake, you can type command with schedule in system crontab, but it helps nothing, just pushes determining problem away.

Thank you for your help, to execute this command I just have to use PuTTy then connect to SSH and login etc, then just type this command? That's it? No need to typing it after each reboot? And what if I want to undo this command what should I do?

And about schedule reboot just forget about it, I usually like to restart my routers/mesh once a week to make everything works as expected because all electronic devices needs this from time to time, I have a 5G router which have this feature built-in and if I leave it on for a week without any restart the speeds drop and I'll have ping spikes etc, I don't know what is the cause of these problems but a simple scheduled restart every week solves 99% of these problems.

periodic reboot, but should not be necessary