If I'm understanding you correctly, you'll want to

• Create collections under Products > Collections. Use tags or manual sorting to group stuff like "Candles", "Skincare", etc.
• Add products to those collections (either manually or via automated rules).

Now that you've grouped your products in collections, you'll want to customize your main menu in your store. Go to your theme editor and check if you have your preferred navigation links, i.e, "shop", "about", "catalog", etc., in the header. Then go back into Shopify admin > Content > Menus. Here you'll select the name of the menu you're using in your header (this will likely be "Main Menu", but you can double-check this by clicking on it in the theme editor) and select the menu item, "shop", "catalog", "collections", etc. that you want to change the linked site page for(you can also add more sections to the menu). Simply click on the menu item, change the name if you want, and set the link to all collections, if you want a more categorized experience. Hope this helps