Try the lessons section. It is helpful because they are small lists that you can focus on until you pass the quiz for one lesson and move onto the next one. Since you are level 1, doing the practise page is sort of like doing 20 of those lessons all at once, because the practise page is to practise all of the content of the unlocked lessons together.
If you still have difficulty even after doing the lessons, try adding another thing to help you learn along side JCJP. What you supplement it with is up to what your best learning method is, such as practising handwriting the answers you get wrong. You could also use the notes section of JCJP to make a list there of the words/kanji you keep getting wrong.
The reading section is good for reinforcing your knowledge as well, since it puts what you've learned in the context of sentences. If I recall correctly it's not unlocked right away, so you may need to earn exp to unlock this part of the site.