Define Validation Rules for S/4 HANA Cloud

Dear Gurus,

I need to know how define validation rules in S/4 Hana Cloud, I find the following OSS note Define validation rules but it's looks like regarding just S/4 HANA and also I didn't found the app "Define validation rules" in the starter system as indicated in this note

Cloud you please indicate the right way for it?

Thanks & Regards

M.