The Que itself means nothing. You can say " tenho que estudar" or "tenho de estudar" ( I have to study). It's the same.

Thank you both! I still am working to understand , but These explinations have helped a lot.

2 comment: I think understanding this is kind of difficult, native speakers usually don't know these grammar details. I'll try to explain it better. First of all, we have different types of sentences. Some of them are independent, and others only make sense because of main sentences. Those other ones are called "orações subordinativas" (something like subordinate clause/sentence). And there are different types of "orações subordinativas". They can be used, for example, as an object, if the object of the main sentence is an action (a verb).That's exactly the case you mentioned.

I'm not a teacher too, neither do I know much about Portuguese, but I would say it is a "conjunção integrante" that unites the main phrase with the second phrase, which is a "oração subordinada substantiva objetiva indireta". It means this second prhase is the indirect object of the main phrase. For example "I have to do my homework" > "I have (...)" is the main phrase and "do my homework" would be the indirect object. Sorry I don't know how to say that in English, I don't even know if there is something similar in English grammar.

Hello, The "que" in that sentence is used to introduce a noum clause, so that you can make sense of what "I have to...(?)" It's like you're introducing what you're going to say next...it makes the connection between the two sentences. You see, there's not a precise translation from one sentence to another. The "que" in Portuguese is usually equivalent to "that" in English, but not in your case. I don't known the correct terms here because I'm not a teacher...just trying to help.