Welcome to the iNaturalist forum @sonukumar055.
To get a genus added to the iNaturalist taxonomy, go to the taxon page for the Family (or next higher taxon) to which the genus belongs. On the right-hand side of the page, click on Curation, then Flag for Curation. For the flag reason, say something like “please add genus X.” In the comment, please provide the reason / justification for adding the genus.
Note that iNaturalist follows standard global taxonomic references for most groups. If the genus you want to add is not accepted by the standard in use, some discussion and justification will be needed in the flag comments before a decision can be made.