The reasons for this can cover hardware or software, or misconfiguration. But, before getting any deeper, one major cause of the symptoms, seldom mentioned, is a failing battery.
If any cells in the battery are beginning to break down,. the CPU and ram struggle to keep the computer operating, causing your problem. If you have a battery monitor GUI, does it look OK?
Looking at your process monitor, however, I presume you are using FIrefox? It is using an extraordinary amount of resource! Try IE, in the first instance/test, and see if there is any difference. But your post was not specific as to whether this was generally, or only a browsing problem?? If the latter, then that could be it.
What do you mean by
" I've also tried msconfig and it worked but stopped my sound and internet from working."
What did you do in that window? A picture of your Msconfig - startup, tab will help also, if you are able to access it.