I googled however if anyone has any customized simple presentation/document that covers 5G basics, frequency band details, antenna design etc.. for the beginners, kindly share.
The Frequencies linked in the presentation are representing only a very small percentage of 5G-NR bands defined in 3GPP. Basically, nearly all LTE bands can be used for 5G-NR, plus some extra Sub8 bands (below 8GHz) plus the millimeter wave bands (24-60GHz). A good source can be found here, https://www.sqimway.com/nr_band.php which covers 3GPP Release 16.
The website links to the 3GPP specification, which is not really for beginners...
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