Hello @Ramki ,
Teams Export APIs are currently in preview
As mentioned in perquisites, you should be having required licenses. If you are have the required license you need to fill the form to request access.
Once you have got the access then you should be able to call this API easily: Teams export APIs.
Document is very clear about the steps, if you still facing any issue let us know.
Thanks,
Hunaid Hanfee
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