Can you please tell if the word choice is correct and how I can improve it?

In particular, I'd like you to consider the words in parentheses, too

1) I spent the first days of my Christmas holidays doing homework and studying
2) During the first weekend of my holidays, I went to the seaside with my parents. The weather was fine, and we enjoyed going for walks and buying the last Christmas presents.
3) On Christmas Eve, I first went to the midnight mass, and then I had some hot chocolate with my friends. After that, I went back home and I opened (I unwrapped) my Christmas presents. I was surprised (pleased?) to receive a pair of sunglasses and a pair of jeans
4) I spent the rest of my holidays going to pubs with my friends for a drink.
5) I liked (enjoyed) going to pubs with my friends for a beer (drink), or spending some time with them at home.
5) On 7 January I returned to school and I was a bit unhappy because I had to get up early again. I was also content (?) though, because I had spent a lot of time with my family and friends.
6)On the first day of holiday, (or of my holidays, and not on my first holiday's day?) On Christmas day, I had a big (?) lunch with my family and then we opened the presents under the Christmas tree. I spent the rest of my holidays going shopping in different shopping malls in my area.
7) On the first days of January I finished my homework (and not I did the last part of my homework)
8) I went to a party. I was very satisfied (excited? It was a nice experience for me) because I had the opportunity to meet new people (or to get to know) and make new friends
9) I stayed there for three days OR I spent three days there.
10 ) I spent the rest of my holidays finishing (?) my homework and studying (or preparing?) for a test.

6. "first day of holiday," = either "first day of my holiday" or plural as you have in parentheses.

7. (and not I did the last part of my homework) = bad word order = and I did not do the last part of my homework.

Everything else is fine, whether you use what you wrote first or what you added in parentheses.

Sra

1) The word choice in this sentence is correct. It conveys the idea that the person spent the initial days of their Christmas holidays doing homework and studying.

2) The word choice in this sentence is also correct. The usage of "weekend" correctly indicates a specific period of time during the holidays.
3) The word choice in this sentence is mostly correct. You can improve it by replacing "opened" with "unwrapped" to more specifically describe the action of taking off the wrapping paper from the presents. Additionally, instead of "surprised," you can use "pleased" to indicate a positive reaction to receiving the sunglasses and jeans.
4) The word choice in this sentence is correct. It indicates that the person spent the remaining time of their holidays by going to pubs with friends for a drink.
5) The word choice in this sentence is mostly correct. You can use "enjoyed" instead of "liked" to indicate a higher level of satisfaction. For the second part, "beer" is a suitable word choice, but "drink" is more general and can be used as well.
6) The word choice in this sentence is mostly correct. Instead of "content," you can use "pleased" or "satisfied" to indicate a positive feeling. For the first part, using "first day of my holidays" is more appropriate rather than using "my first holiday's day." Lastly, you can use "lunch" instead of "big lunch" to maintain clarity.
7) The word choice in this sentence is correct. "Finished" conveys the idea of completing the homework.
8) The word choice in this sentence is mostly correct. For expressing excitement, "excited" is suitable. Additionally, instead of "opportunity to meet new people," you may use "chance to make new friends" to better align with the context.
9) Both options, "stayed there for three days" and "spent three days there," are correct and convey the same meaning.
10) The word choice in this sentence is mostly correct. Instead of "finishing," you can use "completing" to more specifically describe the action. Also, "preparing" is an appropriate word choice for studying for a test.