
Hi @Vinod Survase,
Thank you for posting in this community.
Please make sure that you are a global administrator.
First, you can go to Admin > Users > Guest users to see all the guests in your organization.
Second, if you want to know if a site is accessible to external guests, go to Admin > Show all > SharePoint > Sites > Active sites. Click on the site's name > Membership > Members. All users whose e-mail addresses do not end with @your_tenant.onmicrosoft.com
are guests.
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