1.Would the raw data(SQL data) transform into the web?
Afaik you cannot connect a Qlik Sense app in the free version of Qlik Cloud with an SQL server. You can only use data files that you upload.
2.And can I set the purview for some people can't see the raw data ?
Yes, simply don't give them the data file you uploaded too.
3.(Only can share data for five people?)
Yes, only five people.
4.(We consider the data security, if the data(SQL data) would be transfer into web,
to buy Qlik View will solve this problem? I want to know what different between them in basically.
Qlikview is not a cloud app. You install and run it in your organisational infrastructure. The free version of Qlik Cloud is a Qlik Sense Server installation that is cloud based and offers limited functionality. It is not meant for enterprise usage. Ask for the paid version Qlik Sense Cloud Plus instead.