I would recommend starting with the MMFA cookbook - https://community.ibm.com/community/user/blogs/kerry-gunn1/2022/11/29/mobile-multi-factor-authentication-ibm-verify-mfa
Your question is fairly broad, but you'll need to configure your auth mechanisms and an auth policy at minimum, then integrate WebSEAL with AAC. You an either choose to apply the policies at the object space or setup WebSEAL so that it invokes your auth policy for an AuthN/login event. Most of all this is covered in the MMFA cookbook in some form.
Once you get a basic policy working, then work towards adding complexity around your access needs.
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Matt Jenkins
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