Below are specific to the original Issue at hand and a few addition important possible issues worthy of mention.
Problem: Other problem
Description: High kernel task usage
Major Issues:
Q - No Time Machine backup - Time Machine backup not found.
Q - Time Machine Not Configured!
A - User choice but running a computer without some type of Data Protection is risky. Time Machine Backup is very useful and can be used to Revert to Previous Working macOS
Q - Kernel panics - This system has experienced kernel panics that could be related to 3rd party software.
Q - Kernel panics - This system has experienced kernel panics. This could be a sign of hardware failure.
A - Either of the two above are troublesome at least but is amplified by not having Data Protection in place.
A - Hardware failures do occur and generally increase with age of the computer
A - To rule OUT Hardware failures -->> Have the computer evaluated by the Professionals who have the Special Hardware / Software and Expertise to diagnose the issue and offer possible solutions
Minor Issues:
Q - High battery cycle count - Your battery may be losing capacity.
Q - Battery: Health = Normal - Cycle count = 1281
A - Batteries are considered Consumable Products. Over time it will degrade to a point where it needs to be replaced. The usage is normal as the capacity will go up and down all the time and never stay always at 100%. Apple Batteries are rated for 1000 Full Battery Cycles and / or 80% Capacity before needing Evaluation or replacement.
Q - Unsigned files - There are unsigned software files installed. These files could be old, incompatible, and cause problems. They should be reviewed.
A - Self explanatory and bears the Users attention and to be actioned
Q - 32-bit Apps - This computer has 32-bits apps will not work on current versions of the operating system.
A - Self explanatory and bears the Users attention and to be actioned.
A - Here I call upon the more learned contributor @BDAqua for guidance
Drives:
Q - disk0 - APPLE SSD SM0128G 121.33 GB (Solid State - TRIM: Yes)
Free: 46.13 GB
Available: 49.60 GB
A - it is suggested to keep at least 15% to 20% of the Drive Total Capacity as Empty Space for good operations of the computer
Q - 8 GB RAM - Not upgradeable
Q - /Library/Application Support/VirtualBox
A - Running High Sierra alone is fine with this amount of RAM but running it with a VM Software like Virtual Box is going to be a great challenge for this MacBook Air and only 8 GB RAM.
Q - [Loaded] com.google.keystone.agent.plist (Google LLC - installed 2022-04-19)
A - Already covered this issue in separate reply - would suggest reconsidering the usage of Google Chrome
Top Processes Snapshot by CPU:
Q - Google Chrome Helper (Renderer) (10) 46.34 % (Google LLC)
Q - Google Chrome Helper (GPU) 18.42 % (Google LLC)
Q - Google Chrome 8.52 % (Google LLC)
Top Processes Snapshot by Memory:
Q - Google Chrome Helper (Renderer) (11) 1.96 GB (Google LLC)
Q - Google Chrome 373 MB (Google LLC)
Top Processes Snapshot by Energy Use:
Q - Google Chrome Helper (Renderer) (11) 18 (Google LLC)
Q - Google Chrome Helper (GPU) 4 (Google LLC)
