Postcard in English.

Hi guys!
I'm having a great time in Cadiz. It's awesome but the weather is extremely hot. I'm spending my days exploring the local area and trying different foods. Here the fried fish is a quite typical plate.
Here there’re are a lot of beautiful beaches. Yesterday I was in at the bay of Cadiz, I fell in love. I was seeing the grate great sunset while my friends were playing guitar. It was really awesome.
I will send you other postcards.
I’m having a good hollidays. (holiday) [As you’ve originally written it, it seems that you’re wishing your friends a good holiday and I don’t think that’s your intent so I altered it).
Kinds regards for everybody!! (This is okay but you may want to say something such as, “Best wishes for/to everybody” or “Hugs for everybody” since you’re writing friends).
See you soon!!
Andrea

Nicely written Andrea. You write well and you’ve really let your friends know what you’re doing in Cadiz and how much you’re enjoying your time there.

Postcard in English.

Hi guys!
I'm having a great time in Cadiz. It's awesome but the weather is extremly hot. I'm spending my days exploring the local area and trying different foods. Here the fried fish is a quite typical plate.
Here there're a lot of beautiful beaches  There's a lot of beautiful beaches here. Yesterday I was in bay of Cadiz, I fell in love. I was seeing ("watching" sounds a more natural) the grate (great) sunset while my friends were playing guitar. It was really awesome.
I will send you other postcards.
Have a good hollidays.
Kinds regards for  (from)  everybody!!
See you soon!!
Andrea.

Good job this.

- Joshua