Your question should be "Are these sentences correct?" Here is how I would say what you wrote: "Carlos was born in the year 2000. In Spanish, we say 'Carlos nació en el año 2000'." The first sentence was correct, except that you did not end the first part with a period. Where you wrote "if," you should have started a new sentence instead of using a comma. Also, the reason I changed your phrase to "we say," is because Spanish is your native language and when making a reference to something that is commonly said in ones own language, people will start with "we say...." I hope this makes sense, if you need any more help. Please let me know.

Esta perfecto.