There are several ways to get to sap hana SQL scripting. The first one is to follow a private training course either in a training course center or on line.
The advantage is that you will get help and support from an experienced tutor whenever you need it. As well as practicing on a real sap hana database you will be able to use and write certain sap hana specific SQL scripting.
The second opportunity is to follow a sap hana SQL tutorial from a site. It is free and you can read SQL Guideline and explanations a much as you want. However, do not expect to have hands on nor to be able to practice SQLscripting.
Those sites will only offer screen shots and explantation. If by any chance, a free site offers practical exercices, be aware you will be using no more than standard SQL. You will not be connected to sap hana but mostlikely to an open source database.
Finally, there are today many free tutorial videos available. They are very usefull but again unfortunately there is no hands on sap hana scripting.
Looking for structured and organized sap hana SQL tutorials is not easy. So far "SAP HANA Academy" is offering interesting SQL tutorials. Tutorial are simple, short and easy to follow.
Through those videos you will be learning how to handle SQL via hana studio and hana studio SQL console. The explanation how to use hana studio is good and shows how to handle usefull aspects of the tool options.
As far as SQL is concerned, lessons show mostly the use of standard SQL.