My iMac performance is slow

Ok, I have had a chance to do a quick review of the report. As such here are my observations/suggestion, about the potential reasons your Mac's performance is "slow":

• Total system RAM: 8 GB: Your Mac's RAM memory is limited. It would do better with 16 GB or more.
• Fusion Drive: Your Mac's Fusion drive (combination SSD & HDD) appears to be in good shape with plenty of storage space. The "jury is still out" on, whether or not, Fusion drives benefit from being formatted with APFS.
• Configuration Files: /etc/hosts - Count: 1: This section should be empty. The fact that it isn't would indicate that your Mac's hosts file has been modified. Whether that is do to a third-party app, something you did, or malware, I'm not sure at this point. I will reference a few articles, for your reading pleasure, at the end of this post.
• Unsigned Files: Appears that Microsoft Teams has introduced potential malware. I suggest, at this point, to completely remove it.
• Kernel Extensions: CleverFiles Backup Service. If this service is to backup your Mac over the Internet, it could affect overall performance when it runs.
• Launch Daemons: CleverFiles & EaseUS Data Protect Backup. Again these services would affect performance when running. Google Chrome is known to be a memory "hog." I suggest that you try using Brave or FireFox instead.
• Performance: Fusion drive read/write speeds appear to be "normal" for this type of drive.
• Virtual Memory Information: This is where your Mac, with 8 GB of RAM, "rears its ugly head." Note the Swap Used value. It should be zero. The fact it's not means that there is not enough RAM to hold all the apps running at the time of this report. As such, some apps will be swapped out to the Fusion drive. This will definitely cause a performance hit. Potential solution? Add more RAM or run fewer apps simultaneously.
• Clean up: I suggest that you follow the report's advice and remove these no longer needed items. This section lists what those are, and where to find them.
• Diagnostics Information: One Apple process, com.apple.WebKit, had three occurances where it "pushed" your Mac's CPU to its near limit. It appears it just started to happen recently (March 4th). Not necessarily an issue, but I would run EtreCheck again in another few weeks to see if it gets reported again.

Other than what I have commented on, nothing else in the report stands out to be a problem.

I suggest that you run an EtreCheck report, and optionally, post it here if you need assistance with interpreting its results. If you are not familiar with EtreCheck, it is a diagnostics tool, developed by a valued forum member, that greatly aides in troubleshooting difficult Mac issues ... both software & hardware.

Ref: Using EtreCheck to Troubleshoot Potential… - Apple Community

Would really suggest follow the advise from @ Tesserax ensuing the EtreCheck application.

Be aware, the " I even scanned my iMac with Malware checking software " will show up in the report.

Nothing wrong with that but does indicate something on this computer is playing up

Just to add >>

The Application is Not a " Silver Bullet " but only a tool to examine the Hardware / Software used on this computer 

This is a Diagnostic Tool that makes no changes to the computer.

It makes a coherent and readable inventory of both the Hardware and Software used on the computer 

The application is free or paid for added features. 

The Report will Not Reveal Any Personal Information. 

Post back the Full Report - copy and paste - >>>> using the Additional Text Icon  <<<<

Lastly - should you decide to use and post the Report now or at a later time, we are willing to have a very close look and offer some insights 

When the application has generated the report

In the Menu of Etrecheck application, there is a " Share Report "

Use the Copy option

This places the Text of All Details in the report to the Clipboard on your computer.

Then use Additional Text to Paste the contents of Clipboard

In good faith and as an illustration of what a Full Report should look like.

Below is a copy of my recent report

Welcome and yes we see the report

As the suggestion to use Etrecheck application was originally presented by my learned colleague @ Tesserax

I think it better I not interfere but observe.

Am confident they will return to dissect the report in great detail

Welcome 😎