Q: remove megabackup app

I also just uninstalled MalwareBytes because I am not 100% sure it is trustworthy.

No "anti-virus" or "anti-malware" software is trustworthy, and you should never install any software, trustworthy or not, unless it serves some useful purpose, which that doesn't.

The screenshots that you posted don't show any malware, but you may have left out the LaunchAgents folder inside your home library folder.

Please triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination command-C:

~/Library/LaunchAgents

In the Finder, select

          Go ▹ Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. Press return. Either a folder named "LaunchAgents" will open, or you'll get a notice that the folder can't be found. If the folder isn't found, go to the next step.

If the folder does open, press the key combination command-2 to select list view, if it's not already selected. Please don't skip this step.

There should be a column in the Finder window headed Date Modified. Click that heading twice to sort the contents by date with the newest at the top. If necessary, enlarge the window so that all of the contents are showing.

Follow the instructions in this support article under the heading "Take a screenshot of a window." An image file with a name beginning in "Screen Shot" should be saved to the Desktop. Open the screenshot and make sure it's readable. If not, capture a smaller part of the screen showing only what needs to be shown.

Start a reply to this message. Drag the image file into the editing window to upload it. You can also include text in the reply.

Leave the folder open for now.

... I also just uninstalled MalwareBytes because I am not 100% sure it is trustworthy.  Reasonably sure, but not completely sure.  So I took it off.  You can see a LaunchDaemon for it below.

LaunchDaemons are processes called by launchd and operate without any graphical user interface, or what might be described as "in the background". As such it can be difficult or impossible for a user to be aware of what they are doing or to even know they are present. For example, installing Google products such as Google Chrome litters a Mac with a plethora of "helpers" as well as a service that automatically checks for updates and pushes them to your Mac without your knowledge or intervention. Since those processes run at a privileged level, it is capable of performing other tasks known only to Google. Given that Google's sole reason for existence is to harvest personal information from all the Internet-connected devices you use, for purposes known only to it, one can assume that is at least one of its LaunchAgent and LaunchDaemon purposes.

As a rule I do not install those things for several reasons, not the least of which is that they can cause unexpected behavior. The onset of that behavior can appear to be spontaneous, due to the way LaunchDaemons are designed to work. Google Chrome for example remains a notorious, directly attributable cause of poor Mac performance, many years after having first released it for OS X.

You wrote that you uninstalled "MalwareBytes" but as long as a "helper tool" remains installed in LaunchDaemons you cannot be certain of its effects on your Mac or the information it contains. A properly implemented uninstallation utility should remove all components of the program it was designed to remove. For example, Adobe's Flash Player uninstaller does that and will remove those components from your system. As far as I know Google's uninstallation instructions work also. I do not know what "examsoft" does but I assume you know its purpose, that you are certain you need it, and know how to get rid of it when you don't want it any more. You should not install something unless you know the answers to those questions in advance. Not knowing is how adware gets installed to begin with, a subject I address in How to install adware. Recognition and avoidance is the only reliable way to avoid being affected by it.

Another significant concern exists: your Time Machine icon indicates a problem with it that needs to be addressed. If you have a reliable backup created prior to installing "Megabackup" or "Malwarebytes" the easiest way to undo their effects is to restore your entire system, but only you can determine if you have that backup.

I won't address removing "Megabackup" in your case because I do not use Chrome, for the reasons stated above. If you were to ask my opinion it would be a better idea to remove Chrome.

Lastly if you allow others to use your Mac they should at least have their own User accounts, and should not be allowed to administer your Mac unless you want someone else to be able to alter it in the same manner as you. Never share your login password with anyone. Consider using a "managed account" for minor children. Otherwise, you will continue to leave your Mac vulnerable to this sort of problem, or worse. If you want help with any of that write back.