There are in fact several versions of Thunkable available. The default version is called Drag and Drop (DnD). This allows you to drag components to different positions in the Design Tab. The older version which has a few more features is called Snap to Place (StP) and does not allow you to re-position components easily on the Design tab. Rather, you have to be creative with containers such as rows and columns or by manually changing the x/y position values of components.
Thunkable Staff are working to bring the features from StP to the DnD version so unless you have a good reason to use StP, I would stick with the newer interface. Lastly, there is a group of users who are beta testing a new Layout set of components that attempt to bring the rows and columns of StP to the DnD version.
So yes, you may see older videos that show the StP interface which can be a little confusing. Bottom line, if you don’t see something you need, post a screenshot and someone here can help you find it (if it exists) in DnD.
Also, this documentation page might help clear things up a little.