django advice on multiple apps and forms per view

I want to make a web page with Django where people could search through articles and login to post comments. I would also like to include polls app.

This requires multiple form fields per view. Search and login fields should be visible from anywhere. Also when user is logged in, login form should disappear and his name should appear instead. All of this should be happening in base.html (I want it to be visible from everywhere).

I am somewhat beginner in Django and I am struggling to see how to do this. I tried to make different apps and custom tags to include them in base.html. But then I get an error that POST data cannot be rendered via custom tags.

Any ideas and suggestions how to make these multiple forms and multiple apps per page working? I would appreciate any advice!