I have few points to know can you please help me with this.
1.Notify when the new update is available.
2.Need to push on 1 system first
3.Need to alert users 2 or 3 times to install the new updates?
4.Need to force install the updates if the users don't take action on installing the updates manually
Assuming you're referring to macOS updates, check out Nudge. Do a quick search on here and you'll find some threads posted by users that will have some helpful troubleshooting steps resolving some odd problems. Be sure to check out the Jamf Schema when deploying it, makes thing's a lot easier.
If you're asking about updating apps installed on the Mac, check out Jamf's patch management. It's built into Jamf Pro.
I believe you're looking for help with the macOS minor OS updates IE) 10.14 > 10.15 etc. There are a few different ways you can approach this and it depends on what version of macOS your macs are running currently and the macOS version you would like to get them to. I am going to refer you to the Jamf education training videos, these are pretty insightful as you have a video to reference when you are following along and this is probably going to be the easiest way to get started. Check it out below.
If you are wanting to get more advanced and want some more options for installation, check out the URL's below for some insight.
In this url(https://www.jamf.com/blog/reinstall-a-clean-macos-with-one-button/) there is a screenshot in that "install mac os Big Sur.app", what is this means? Whether we are creating any package with name .app or just we are giving the name itself?