Hi Jose and a warm welcome to you.

If I may suggest, start right at the beginning. I say this because, although you are familiar with introductory concepts, you may have picked up some bad habits along the way.

You can quickly run through the Core 1 and 2 sections and refresh your present skills. I am sure you will find something useful to you and stuff you may not have known about. Then, when you feel you have gotten the most out of these sections then you can decide which path to progress on.

By the way, there is a lot more on this site than just the core lessons,. Have a good look around and make a tour of discovery. It's a very rewarding site.

I wish you every success in your endeavours.

Kind regards

Joe.