I have completed the skill tree and am only at level 14. How will I add point to progress to level 25 which is the ultimate goal? Dr. Verde
To the left of your tree is a button "lesson practice", which will give you a timed practice (you can turn the timer off, too) of random sentences. You can also just click on any lesson you want to review and click on the blue button there, or you can go to "vocabulary" above and click on "practice weakest words". All of them will give you skill points.
Yes you can refresh and translate articles but you have a long way to go to get to level 25. Level 25 is an ultimate goal but you don't always have to reach there. I suggest if it gets boring, start a new language or help find French sentences from other webs and contribute them to Duolingo.