MiniCart doesn't show the added product in homepage

For the minicart to work with any cached page, it has to populate the cart from woocommerce ajax. Most themes populate the minicart from php but also implement the js update. In this case a cached page would show an empty cart until the ajax runs when the page is loaded. Not sure why this wouldn’t work on the homepage of your theme unless it’s using a different sidebar or header from the rest of your theme.