Magento 2.4.2 i have to millions of product to import and also reindex it

I am using magento 2.4.2 and uploaded millions of products, now how can I reindex it. Some index easily reindex but catalog_category_product and catalog_product_category tacking time and also it not reindexing even I have left for 24 hours. how can I reindex it and also can see process if possible easily and fast. please tell me if required to change in server configuration or need to install any software.

Also, When I upload product via CSV it not showing instantly it required to reindex.

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