OK, so you decided to plunge in and read some poems. What should you be looking for? Well, chill. I'm going to assume that if you're coming here to read this, you aren't writing professional criticism for a living. You don't need to know a metaphor from a simile, you just need to notice what's going on in the poem.
Let me tell you about a very interesting museum my wife and I visited last spring. It was the National Civil Rights Museum in Memphis, TN. When we went in the ticket agent told us our ticket was good for two days, and we could come back tomorrow at no extra cost if we wanted to. I was surprised, because the building isn't that big. Well, let me tell you, each room had literally thousands of artifacts on the walls. It was difficult to focus on the room's story because it looked like someone had taken a time capsule and exploded the thing, sticking stuff everywhere. I quickly understood why it could take two days to visit this exhibit. But guess what? We didn't need to stop and read every poster, look at every photograph, or pay attention to each diorama. We were able to pick up on the spirit of the place and understand the story of the civil rights movement, even though we didn't notice every single thing there.
When you read a poem, have the same attitude. Don't worry about missing some of the points. Poems often have multiple ideas going on at the same time, but you don't need to catch all of them to enjoy it. Think of all the movies you've ever enjoyed. Have you ever searched for information about one of those movies on line? You will find people obsessed with details, like why did the director choose a particular picture to be hanging on the wall in the restroom? Right, you didn't even notice that there was a picture hanging on the wall in the restroom, let alone that it was a particular painting by a particular artist.
Still, you managed to enjoy the movie.
Please, go read some poems!