Start with D365 Portals.

For Learning about Portals your D365 Trial is Enough.
To get the trial check my blog here 

Once you have Trial,
Go to Office Portal Login using same credentials you got for D365

Click Admin App, this will take you to admin portal of Office 365.
Now Navigate to Dynamics 365 Instance picker shown in below slide show

Actually, you can directly login to Instance picker as well, but URL vary from region to region, so best way to navigate is through Office Admin Portal.

In Instance Picker you have option to Select Instance, Update Instance, Check Service Health, Backup and Restore And list of Application you can have to your instance.

D365 Portals in not enable for any D365 Instance by default.
You as an Admin user have to manually enable it.
So, In d365 we have something called solution, which is nothing but the collections of component and sub component.
Components can be anything in CRM, like Entities, dashboards, process etc.

So, Portal is also provided as a solution by Microsoft.
it is not in CRM by default, To check, Select your trial instance and click Open and you will get your CRM Administration Area Open.

In CRM, Navigate to Setting > Solutions. and Search for solution with name portals, You will find none.

Now again come back to Instance picker Tab, Select Instance and you will find option to select solution, List of Solution has installed and can be installed to this instance.

Click this Solution and this will open of the list of Solution available for current instance.

Base Portal – a Portal with Nothing, Just some configuration to get started.
Base Portal can be used once you advance D365 Portal and want to develop something of your own.

Community Portal – As it states, a Portal for community, so it has some entities mapped and you get knowledge base.

Custom Portal/Customer Portal – a Portal which we will install, This Portal is widely used, as it comes with many example template and you can do as many changes you want, it is a custom Portal.

Customer Self-Service Portal – A Portal where Customer get option to report issue/incident/case regarding product or service directly via portal.

Employee Self Service Portal – This can be an internal portal, used only by employees and need D365 Licences.

Partner Portal/Partner Portal for Field Service – This is also like Employee Self Service, where your Companies partner can access and see data without getting and understanding of CRM.
This also required CRM Licences

We will install Custom Portal.
To install, Select Dynamics 365 Portals – Custom Portal and Click Install
This will ask to access Terms and condition, Read it and accept it.

Once you Access, Installation process will be begin on server, it will take quite long, so you can close and come after few hours.

Once Installed, status of that custom Portal solution will be installed. 

We can install and configure portal from application tab as well.
This is similar to installing portal from solutions list but with more options of configuration.
Click on Application Tab, Select Portal Add-On, status will be not configured.
So click Manage and start configuration.

Add Name to your Portal, Specify Portal URL related to your name and select the instance for which you added the custom portal solution.
Name – Broker Agency Consumer Portal
Url – brokeragencyindia
Instance – dphone
Selecting instance will give more options like,
Language –English for me
Administrator- MySelf
Portal audience – Customer or Partner or employees, Select any
Select type of portal we want, i choose custom portal, try installing different to explore

Note – You get only one free portal with one instance, so to get more you can take more trial.

Once Portal is installed and configured, you will see below screen with all the details and others options

Portal Details – This has basic information and very important, The URL which is the url of your Portal.
Portal Action – This is list of action you can take like logging, Error handling, Tracing, Restarting, Resetting etc
Manage D365 Instace – Allow you to switch between instances.
Set up sharepoint/BI integration – as names states.

Portal is installed, just copy that link and browse your Portal.
We will take about how to access portal, sign in, Register using multiple authentication mode. Creating Entity forms and views,
Using Liquid Template for customizing portal in upcoming blogs.

Thanks