How can I set single column layout for woocommerce products page by default.
and remaining other pages/posts of website as global settings (two column layout).
WooCommerce tells WordPress that the products page is a type of blog, so as of right now, the “Blog Layout” option in the Customizer controls the layout of that page.
One thing you may be able to do is create a new page, and then display products on it using the provided shortcodes from WooCommerce.
I may look into making it super easy to choose a custom layout for this page in the future – will have to look into it a bit.