How can I make my website mobile ready?

I need to make my website mobile ready. I want my customers to take a picture of a product with their phone or tablet and be able to upload one and multilple pictures and list that product to be sold.

1. Take Pictures of item.
2. Upload single and multiple pictures of item.
3. list for sale with price.
4. sell item and make money.

Is there a plugin that does this or do we have to create code?