server keeps spiking over 1,300%

my server keeps spiking to very high loads and other sites open apart from one site which takes a lot of time to

i have doing every MySQL setting and PHP configs i know but still spikes and drops

here is the htop

i had to enable underattack mode to be able to access the site a bit
this only happens when i move a particular website on my server to a new domain

Hello. Please check the site's logs for analysis. This should be caused by an attack.