Can any one of please let me know what is the step by step process of migrating SharePoint 2010 to SharePoint online with out using any third party component?
I'm afraid this is going to be a "Very" time consuming and manual activity.
PowerShell for SharePoint online is currently limited.
You could use it to create your site structure but after that you are configuring content and metadata pretty much manually.
If you have a lot of content it may end up being cheaper and safer to purchase a third party tool.