I know there will be no Windows 11 (as far as i know), It’ll come as updates for windows 10, what i want to know is “Is there a specific release Date for this update, will it be MAJOR UPDATE changing everything, or just minor updates like step by step ?!” 

some websites say that It’ll be in 2018, but nothing is confirmed.

If there be any updates on Windows 11, they will be posted on official Windows Blog.

Atm, there is no confirm information on Windows 11 that can be provided. Microsoft is currently focusing on Windows 10 and improving it in successive versions. Windows 10 Semi-Annual Channel is governed by the Modern Lifecycle Policy. Feature updates will be released twice a year for Windows 10 via the Semi-Annual Channel, targeting March and September annually. 

Read more in this support article: https://support.microsoft.com/en-in/help/13853/windows-lifecycle-fact-sheet

IMO, these feature updates released will ensure customers continue to receive support for their Windows 10 versions. And that would eventually reduce chances of having Windows 11.