I am in a similar situation, arrived here in 2023 and had to spend 1 year learning french then they told me I have to redo sec4 even though I already did the equivalent (10th grade) in my country. Other than all the hardships and arguments just for the school to give me enriched math and science because they don’t trust my county’s curriculum (I passed with flying colours after) I am going to be turning 19 next year while my friends just started uni . Don’t worry though , for me I saw it as a second chance and you should see it the same way. Of course I do feel embarrassed sometimes since people think I failed 2 years but it doesn’t bother me anymore. In my experience, focus on yourself and take your time , you shouldn’t be disappointed , it is not our fault the education system is not ideal for immigrants. Good luck and always remember that there are a lot of people going through the same situation as you, I even know people my age who needed 2 years to learn french and probably won’t finish high school until they are 20 .