Why should you care about Azure AD B2C, you can read here.
To follow along you need to create Azure Account. Read this blog post how to do it.
Log in to your Azure Account
Click on Create a resource and start typing azure ac
Choose Azure Active Directory B2C
Click on Create
Now we have to create new Azure AD B2C Tenant
Click on Create a new Azure AD B2C Tenant
Choose organisation name, domain name and Country.
I chose dotnetb2c as organization name and domain. I leave in Norway, so I picked this choice. Wait a while and the tenant is created.
Now click on Link an existing Azure AD B2C Tenant to my Azure subscription
Choose Tenant we just created
Choose subscription and Resource Group. I have only one subscription called sergeydotnet and I choose to create a new Resource Group.
Click on blue text Create new and provide the Name
Choose also location for Resource Group
Click on Create.
Now if you click on All resources
You see your Azure AD B2C Tenant.