(1) If Windows Updates is showing you more than one update (occurs for different Windows items like Defender and Feature for example - different) you can select which ones you wish to do now and which later.
Unless you are on a business LTS or other business license, you do have to do all updates at some point.
(2) If you have downloaded some updates and stop the process (however you stop the download), what you have downloaded will update. The partial download will restart downloading at a later time.
(3) Once a download is complete and Windows wishes to install, you can postpone installation at that point for a number of days.
If installation has occurred, you must restart, but even that can be postponed to a later time or the overnight restart time
It is generally better to allow updates to download and not interrupt them.
You can organize update and install time with Windows 10 Update scheduling. There is now (for quite a while) no need to have restarts interrupt your work.
Good luck with scheduling.