I watch different reality shows, principalmostly in English.

principally is ok but incredibly format, using mainly, mostly, or usually would all work as a substitute

And lately, I have followed their fights inthrough other social media.

using with or through is grammatically correct here. Also general rule is to not start a sentence with and or because :)

Also, it shows different stereotypes about many cultures, and it is interesting to watch how Colombian people seem toare seen by North American eyes.

just another option that flows a bit better

And also, they show the Colombian gastronomy and. I can learn new tips to cook.

I watch different reality shows, principalmainly in English.

principally sounds formal

I watch 90 day fiancé, there I learnand listen to informal conversations and English in different accents.

I corrected this to give an idea of something more casual

It isn't not the only reality show that I watch, I like Makeup or Cooking competitions.

And also, they show the Colombian gastronomy and I can learn new tips tofor cooking.

I am going to write my answer with informal English, it is my goal, I don't wan. My goal is not to be perfect but understandable.

I feel that with my English level, I've unlocked a new universe of gossip, hahaha.

And lately, I have followed their fights ion other social media.

It isn't not the only reality show that I watch, I like Makeup or Cooking competitions.