Hello Bruno.
Welcome to JustinGuitar and the Community. It’s great you have found Justin’s lessons, he offers structure and a sure path to follow from the very beginning. Thousands and thousands have learned using his lessons. Thanks for taking a subscription to the App. It is definitely worth checking the matching lessons on the website. All have additional information, some downloadable content and each has a link to a dedicated discussion topic here in the community.
If you need any help with a lesson specific question or with any general guitar learning question then do not hesitate to ask. There are many good folk here who will happily offer help and encouragement to those coming up behind them on Justin’s Beginner Courses. They embody and carry the pay-it-forward ethos we have nurtured for many years in our community. There are many old hands too who have years and (hopefully) a bit of wisdom they can bring as they give their support to those hitting the road blocks - which we all do.
It’s worth checking out all the other old dogs too:
Just ask if you need anything.
Cheers 
| Richard_close2u | JustinGuitar Official Guide, Approved Teacher & Community Moderator.