I need to turn these sentences (or notes) into a cohesive paragraph, using sentence connectors instead of points and improving the word choice. Could you please help me?

Robinson’s education of Friday recalls the processes of modern colonialism, which follows a recurrent pattern:

1) The island turns out to be the ideal place for him to prove his qualities as a coloniser as well as a hero. As a matter of fact, he manages on the one hand to exploit and dominate nature and on the other to shape his own destiny through his work and through the interpretation of his achievements in the light of the Bible. He is convinced to have God on his side.
2) Name giving: he gives Friday a new name which is meant always to remind the Indian of his debt to the white man (he was saved by Robinson on a Friday); Friday, on the other hand, must call him master. (rephrase)
3) New European clothes: Robinson covers Friday’s nakedness by giving him worn-out European clothes; Friday “was very pleased to see himself almost as well dressed as his master”.
4) New European language: Robinson does not bother to learn Friday’s language but teaches him enough English to understand him and follow his orders.
5) New religion: Robinson teachers Friday the principles of Christianity.
6) Technical superiority: Robinson never gives Friday a weapon and is even careful never to let him see how he loads his gun. In short, Robinson has over Friday (the colonizer) three great advantages: a technical advantage
8) (Robinson has weapons and more sophisticated utensils); a linguistic advantage (they only communicate in Robinson’s own language); a cultural advantage (Friday is made to admit that his nation’s god is inferior to the Christian God).

Do you think it is a good thing to include parts of sentence in parentheses when writing a paragraph?

I'd avoid putting anything in parentheses. If the idea doesn't fit into the text, then just omit it. If you don't want to omit it, then find a way to make it fit.

Robinson’s education of Friday recalls the processes of modern colonialism, which follows a recurrent pattern: First, he manages to exploit and dominate nature, as well as shape his own destiny through his work and the interpretation of his achievements in the light of the Bible. He is convinced he has God on his side. Second, he gives Friday a new name which is meant always to remind the Indian of his debt to the white man for saving him on a Friday; Friday, on the other hand, must call Crusoe master. Third, Robinson clothed Friday by giving him worn-out European clothes; Friday “was very pleased to see himself almost as well dressed as his master.” Fourth, Robinson does not bother to learn Friday’s language, but teaches him enough English to understand him and follow his orders. He also teaches Friday the principles of Christianity. Last, Robinson never gives Friday a weapon and is even careful never to let him see how he loads his gun. In short, Robinson has three great advantages over Friday: a technical advantage in his superior weapons and utensils; a linguistic advantage, speaking only in English; and a spiritual and religious advantage in Christianity. The island turns out to be the ideal place for Robinson to prove himself as a colonizer and a hero.

To turn these sentences into a cohesive paragraph, we can use sentence connectors and improve word choice. Here's the revised paragraph:

Robinson's education of Friday reflects the processes of modern colonialism, following a recurrent pattern. Firstly, the island proves to be an ideal place for Robinson to showcase his qualities as both a colonizer and a hero. He effectively exploits and dominates nature, while also shaping his own destiny through hard work and interpreting his achievements in the light of the Bible, firmly believing that God is on his side. Secondly, Robinson renames Friday, always reminding the Indian of his indebtedness to the white man for saving him on a Friday. In return, Friday must address Robinson as master. Furthermore, Robinson covers Friday's nakedness by giving him worn-out European clothes, leading Friday to feel gratified in being almost as well-dressed as his master. Additionally, rather than make an effort to learn Friday's language, Robinson teaches him enough English to understand and follow his orders. As part of his colonial influence, Robinson also imparts the principles of Christianity to Friday, introducing him to a new religion. Finally, Robinson maintains significant advantages over Friday as the colonizer. He never supplies Friday with a weapon, keeping him unaware of how he loads his gun. In summary, Robinson's technical superiority, linguistic dominance (as they only communicate in Robinson's language), and cultural superiority (as Friday is made to admit the inferiority of his nation's god compared to the Christian God) establish his power over Friday.

Regarding your second question, it is generally not recommended to include parts of sentences in parentheses when writing a paragraph, especially for academic or formal writing. Parentheses are more commonly used for supplementary information that is not essential to the sentence's main flow. In this case, incorporating the parts of sentence that are currently in parentheses into the paragraph improves clarity and ensures a smoother narrative.