Priya,
Here are a few resources to help you get started:
https://community.servicenow.com/community?id=community_blog&sys_id=30aeafa2db013b04fece0b55ca961925
https://community.servicenow.com/community?id=community_question&sys_id=1822b570db453b4013b5...
While initiating chat, pass the required skills through chat context variables LiveAgent_mandatory_skills (for mandatory skills) or LiveAgent_optional_skills (for optional skills)
You can see the list of supported context variables and add addition...