How do I move to the next level?
I have passed or tested out of the first so many Spanish lessons on duolingo, but I am not able to continue. 'Present 1' and further lessons are greyed out / closed. What do I do to open these?
You have to pass all the lessons in all the earlier skills before later, greyed out skills, are unlocked.
So basically, go into every skill that you've supposedly done (or tested out of) and make sure that you've done every single lesson. You're looking for ones that say "start" rather than "repeat."