One of the best monsters

I usually sit at a monster. I'm not alone but with friends. We all like this place because the monster is simply nice. A place for us to meet each other. I'm sitting on it right now and we all are talking, having fun. This feeling can't be describe. We absolutely have been fun.

What is the monster actually? Is it a sofa or something? :/

One of the best monitors. Or (I have one of the best monitors.) (Unless you really did mean monster lol)

I usually sit at a monitor. I'm not alone because I have my friends. We all like this building because the moniter is a nice place to meet each other. I'm now sitting in front of a monitor. All of us talking with each other has been fun but I don't know how to describe our feelings. We had a lot of fun talking with each other.

I'm not entirely sure what you meant in the third sentence. A better example, if you're talking about a building, would be: We all like this building because it's a nice place to meet each other.

To make this entry better, try explaining 'why' you are doing something. Why are you sitting behind a monitor? Do your friends have to do this too? What building are you going to? Maybe explain why you had fun as well as other descriptive things that will give your English more depth and meaning behind it. Good job so far!