magento246: How to redirect only homepage of website to another website using .htaccess?

I’m trying to redirect my homepage http://magento246.local/ to http://magento245.local/

but

• http://magento246.local/admin
• http://magento246.local/products/

and other URLs after slash should work as and they should not redirect to another website. only the homepage should redirect when someone tries to access the homepage. but if he adds an extra URL with the homepage then it should not redirect.
All this should work through .htaccess file customization.