How do I post to my blog that came with the template? And how do I populate the Best Sellers module?

Hi John,

Thanks for your interest in MultiStore.

How do I post to my blog that came with the template? 

Please refer to product documentation page 3 and 4.

And how do I populate the Best Sellers module?

In OpenCart bestsellers are products with the most sales. You can populate the bestsellers by making purchases (with option to pay on delivery for the products, so you dont actually buy your own products)