My English class

When I went to school I was really disgusted with studying English. I suppose that it was because I didn't understand the lesson. (Class or lesson is okay here but you do not need both words: only one.) At the end, I finished the school with a bad mark in that course.
Years later, I noticed that English is very important for our profession. Also when you travel to another country and want to meet foreigners people. (Foreigners is a noun. Foreign is an adjective. So, "foreign people" is correct, though it's sounds strange.)
In my first trip, I lost the opportunity to exchange language with others. I remember that I was only able to communicate with sign: it was awful! I regret not seizing my English class. Trips encourage me to study English seriously again.

(Not sure if you meant trips in general or this one trip, in which case "This trip encouraged me" is correct.)

When I returned to my country I signed into an academy and studied English everyday for three hours. Well, I can communicate, but I need more practise to improve my English.
Then in my second trip, I felt more confident and I can spend time with my new friends, doing different activities. Now, in my trips I only want to chill out and enjoy the landscape with them.

(With the use of "them", which is plural, "friends" must also be plural.)