imac 2017 desktop ventura 13.0.1 21" slow,

First, there is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This documents describe what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community and Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support.  

There are no known viruses, i.e. self propagating, for Macs.  There are, however, adware and malware which require the user to install although unwittingly most of the time thru sneaky links, etc.   

Anti Virus developers try to group all types as viruses into their ad campaigns of fear.  They do a poor job of the detecting and isolating the adware and malware.  Since there are no viruses these apps use up a lot of system resources searching for what is non-existent and adversely affect system and app performance.

There is one app, Malwarebytes, which was developed by a long time contributor to these forums and a highly respected member of the computer security community, that is designed solely to seek out adware and known malware and remove it.  The free version is more than adequate for most users.  

That being said understand the the Mac you purchased was, at the time, the slowest Mac offered by Apple: 8 GB RAM and a 5400 rpm hard drive. You can't upgrade the RAM but you could get an external SSD, clone your boot drive to it with Carbon Copy Cloner and then boot and run from the external SSD. You could increase the boot, app launch, file opening and saving ties by approx 8x or more. Your current speeds are:

Write speed: 41 MB/s

Read speed: 50 MB/s

That might indicate that the rotational HD is beginning to fail.

I recommend drives from OWC (MacSales.com) as they have proven reliability, excellent customer support and warranties. 

For your particular model contact OWC's customer support and get their recommendation for the SSD model that would best suit your iMac model, work requirements and budget.  T

You should uninstall Antivirus One, Cleaner One, Cleaner One Pro and VirusBarrier Scanner according to the developers instructions. They are unnecessary and only take up system resources.

I would start your own topic, read the following user tip and restate your question/problem in detail: 

     Writing an Effective Apple Support Communities Question - Apple Community

Also include an Etrecheck report.

+1

Your USB 3-equipped Mac with a hard disk or Fusion Drive can have improved system performance by connecting to an external solid-state drive (also known as an SSD).

An external SSD as your startup disk can give your Mac additional performance for system responsiveness, apps, startup, and more. An SSD will make your Mac 10 to 40 times faster for storage, and in turn, make your entire Mac faster and more capable.

To learn more, see Use an external SSD as your startup disk with your iMac or Mac mini - Apple Community. 

Another option is to replace this Mac with a new Apple Silicon Mac: Mac - Apple. You can also use Apple Trade-In to get credit towards a new Mac: Apple Trade In - Apple.

Jack

Download and run Etrecheck. Be sure to give it Full Disk access before running.

Copy and paste the results into your reply. Etrecheck is a diagnostic tool that was developed by one of the most respected users here in the ASC and recommended by Apple Support  to provide a snapshot of the system and help identify the more obvious culprits that can adversely affect a Mac's performance.

Copy the report

and use the Additional Text button to paste the report in your reply.

Then we can evaluate the report to see if we can determine the cause of the problem.