Welcome to the Q&A Forum

Solution:

1. Download "All in one SEO" plugin

2. Go to plugin settings. Check these settings:

Use no inxex for  -categories

-tags

-search   (!)

-Achieves

That will prevent duplicate content issues if you use Wordpress.

Both like and share are great benefit for your business, but if you must chose one, it really depends what do you need.

Like = It's a vote for your brand, this is better if you are looking for long term authority building

Share = This is great if you have some content with viral potential, it can grow fast. But if you don't have viral content, it's good for generating some traffic burst.

My choice is to use like for promoting business homepage and use shares to promote blog posts.

I hope I helped!