Translation of certainty in Spanish

Hi,I'd like to ask you if it's possible for you to tell me briefly how to study here. I don't know that's why I'm not online most of the time. Thank you very much for choosing me as a friend. I hope our friendship can get better so we can practice.
Hi! Thank you for your invitation and for your very kind messages. I'm sorry but it is very late here and I prefer to write you tomorrow. When is the best time to chat? See you later than.
The next day we had the feeling that the worst of our altitude thickness was over and decided to take the local bus to the Sacred Valley, a key area of settlement to the Incas.