The word 'substantiel' is not an English word; it appears to be French, meaning 'substantial' in English. In English, 'substantial' means of considerable importance, size, or worth. adjective
The company made a substantial profit last year.
She received a substantial amount of support from her friends.
In a different context, 'substantial' can also mean strongly built or made. adjective
The house was built on a substantial foundation.
He wore a coat made of substantial material to keep warm in the winter.
Additionally, 'substantial' can refer to something concerning the essentials of something. adjective
The report provided substantial information on the issue.
They had a substantial discussion about the future of the project.