Don’t worry, for Windows update, the later updates will include all contents of previous updates, so install the latest update and SSU is enough.
For your device, just check for updates until your system is up to date, don’t need to care which update is installed and which is not.
Go to this website to check the latest build number, for 20H2 version, it’s March 18, 2021—KB5001649 (OS Builds 19041.870 and 19042.870)
https://support.microsoft.com/en-us/topic/march-18-2021-kb5001649-os-builds-19041-870-and-19042-870-out-of-band-ebbe0617-3a63-467a-aaaa-2a4c68a6de33
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