We have purchased Conditional Addon and we want to apply like "Hidding field options video" but we cant see the option "Field conditional others".
How can we do that ?
CB Conditional has been rewritten since then. Conditions are only applied to the tab or field they are configured on. A field can't be configured to condition a dozen other fields for example. Instead edit those dozen other fields and add conditions to them. You can have as many conditions as you like and it supports AND/OR cases. You can find the parameters under Integrations > CB Conditional when editing your tabs or fields.
Another question will be possible to change the "required" flag of a field using this addon ?
No, CB Conditional can only show/hide tabs and fields.