Added container in default.xml within footer container
<referenceContainer name="footer-container">
<container name="em.maxwidth.content" htmlTag="div" htmlClass="em-maxwidth-content" before="-"/>
<container name="footer" as="footer" label="Page Footer" htmlTag="div" htmlClass="footer_second">
<container name="als-footer-container" label="Als Footer Container" htmlTag="div" htmlClass="container" before="-"> //add container
</container>
</container>
</referenceContainer>
after that create a block and assign block and that block assign to widget with a new container.
But it did not add second level footer.