hidden create button

is it possible in suiteCRM
Version 7.5.1
Sugar Version 6.5.20 (Build 1001)
is it possible hidden some function (create Workflow for example) only for some group of user ?

It is possible but I think you would need to custom code it yourself. I did something similar in the following blog post maybe this will be of help to you:

http://sugarmods.co.uk/make-an-edit-view-field-read-only-based-on-user-role-sugarcrm-ce/