Learn Italian: Tutto ciò significa che la situazione è complicata. - All this means that the situation is complicated.

Ciò is an invariable pronoun that means 'this', 'that', or 'it' when referring to an abstract idea, a general situation, or something previously mentioned, rather than a physical object. The phrase tutto ciò (all this / all of that) is very common in Italian to summarize a whole concept you were just talking about. You could also say tutto questo, but tutto ciò is very natural here.

Could I just say Tutto significa ('Everything means') and leave out ciò?

If you want to say 'All this' or 'All of that', you need the pronoun. Tutto ciò translates directly to 'all this' referring back to a specific (but abstract) situation. If you just say Tutto significa che..., it translates literally to 'Everything means that...', which changes the meaning and sounds a bit unnatural in this context.

We translated 'that the situation' as che la situazione. Why not quella la situazione?

In English, the word 'that' does two different jobs: it can point at a thing ('I want that car') or it can connect two parts of a sentence ('It means that I am late'). In Italian, the pointer is quello/quella and the connector is che. Because 'that' is connecting the two halves of this sentence, you must use the connector che.

Why is it complicata with an -a at the end?