Milos,

I think I understand what you are asking. PowerPoint does not have the same
capability as Word that automatically creates a new slide as you type. You
will have to insert a new slide (Insert > New Slide).

It sounds to me that you might want to reconsider how much text you are
using on your slides.  A good guide to follow (and this rule varies) is to
have no more than 5 bullets per slide and no more than 5 words per bullet.
Even better, try to use an image instead of the bullets. Your text can be
placed in your speaker notes to be used as "voice over."  These approaches
better position you as the content expert (not the slides) and facilitate
better learning among your audience.