Plato's work: What read next?

I always wanted to learn at least the minimum about philosophy, since i love literature and poetry. I was told years ago i should start with Plato, so it is what i did. I've read some dialogues, such is the four dialogues involving Socrates's judgement, The Republic, The Symposium, Memnon, Phaedrus. Then i bought Parmenides, and dude,it was absolutely insane. My head was aching and i could barely understand what they were discussing about. I realized i should take another works to get more familiar with Plato's work. For me the dialogues were never that easy. I often needed to reread the sentences, but taking it slow and writing notes, i think i could take the distance.

I would like some advice on what dialogues read next, or what do you consider the best order to get the idea. It is never easy and it wont give me single answers, but i certainly can get more fluent.