It is not a natural language, it is a constructed language. It was created for a fictional race of aliens (called Klingons) from the Star Trek TV show and movies). There are speakers in many countries, but no country has a particularly large concentration of speakers and there are no native speakers. The practical uses of the language are very limited, but it is a fun hobby. For people who have already learned natural foreign languages it can be a fascinating exploration of language alternatives. For someone learning their first non-native language it can be a good introduction to the topics and processes needed to learn more foreign languages. And if they are a Star Trek fan and this is the motivation they need to start learning about languages, then it makes a nice introduction. Check it out and see what you think!
Be careful of your spelling. Notice the difference between I and l (one has a curl at the bottom). The l belongs between the t and h and the vowel that follows is an I: tlhIngan. Also, that refers to a person that is Klingon. To make it about the language, you have to add the word for "language": tlhIngan Hol.
You cannot and you should be proud to have recognized it. Since "you" in English can be either singular or plural, then without context you can't tell which is meant. Both translations are accepted as correct answers on this exercise.
However, you have made a couple of errors in your post. Note that there is no lower case L in bIqet, it is an upper case i. Duolingo will mark you wrong for using the wrong one, so please look carefully for the small curve at the bottom of the lower case L.
Also note that the S should be written as a capital letter. Duolingo won't mark you wrong for using a small "s", but for people who are used to reading standard Klingon, it is quite annoying to have to read miscapitalized letters. i tYpe ThiS sEnTEncE As aN exAmPle sO YoU cAn SeE wHAt i MeaN.