How can we check if any antivirus is capable of detecting, removing and protecting from the malware? Can it be verified by checking the configuration of the antivirus or by just doing a live scan? If I need to show the evidence that any particular antivirus is working, how can it be done?
The EICAR test file is made just for this purpose. Every signature based malware scanner should detect this file. Everything else just depends on trust.
To check anti virus is capable to detect
Use EICAR test file
you can download it from https://www.ikarussecurity.com/support/virus-info/test-viruses/
simply copy and paste the following string in text file and scan with antivirus
check this post also for Malware database
In order to detect latest virus and malware you need to update the Anti Virus database regularly