@Mgbeke, Oyin (TC/TC) Thanks for reaching out. If you are unable to see your resource group when trying to create an APIM instance, it is possible that you do not have the necessary permissions to view the resource group.
To view a resource group in the Azure portal, you need to have the "Owner" or "Contributor" role assigned to your user account or to a security group that you belong to. If you do not have these roles, you will not be able to see the resource group in the portal.
To check your permissions, you can go to the Azure portal and navigate to the resource group blade. From there, click on "Access control (IAM)" and then "check access". You can then search for your user account or security group and check what roles are assigned to it. If you do not have the necessary roles, you can request that to be assigned to you by an administrator or someone with the necessary permissions.
https://learn.microsoft.com/en-us/azure/role-based-access-control/check-access
let me know incase of further queries, I would be glad to assist you.