The "My Products" page gives you a list of products that you've imported on your Shopify store via MerchMixer dropshipping app.
You can get to that page with a few simple steps:
Click on "Apps" on the left menu of your Shopify Admin
Select "MerchMixer - US Dropshipping".
Click on the "My Products" tab. It shows you the cost of each product and the corresponding profit margin.
You can also look at the details of a particular product by clicking on the "View button". From there, you can see the product's description, shipping time (usually 4-7 days), and the number of units available.
To remove the product from your Shopify store, simply click on the blue "Delete" button.
As for the settings page, it allows you to do three things:
Add your credit card to MerchMixer (it's how you pay vendors for your products whenever you make a sale)
Select/change your MerchMixer subscription plan
Turn product synchronization on/off. Keeping this feature disable will preserve any manual changes you've made to your products — descriptions, pictures, sales prices, etc.