Dreamweaver

You would need sound knowledge of HTML, CSS, JS and a sever language like PHP. a good grasp of least  one of the popular JS frameworks would be helpful too.  If it's a no to these, then you need to look at some other solutions, Webflow seems to be popular these days and would do a lot of the work for you without extensive coding knowledge.

would dreamweaver enable me to build a website where users can create their own accounts and upload videos etc

This is akin to saying would a scalpel enable me to perform an operation?

The short answer is 'Yes'.

You mean you want to build another "YouTube" video sharing site?

Dreamweaver is a very good coding and site management tool.  But nothing in Dreamweaver will do this for you  automagically.  

Look at WordPress and premium video-sharing themes.

https://webdesign.tutsplus.com/articles/best-video-sharing-wordpress-themes--cms-30605

Not really, Dreamweaver is just a basic editor. Unless you know how to code you will be better off sourcing a more advanced bit of software which does have more sophisticated options for amatuers.

Try Wappler editor. Id recommend that for those who arent serious developers, more the 'l have an idea, get rich quick types'. When that idea fails they will just move onto the job which pays the most, almost certainly nothing to do with web development as they have no saleable skills unless they are a sales person and can source their own work.

Wordpress also l believe has numerous plugins that will most likely do what you require.