Golang is used for creating websites Yes. Only expensive sites. Let's say I have a little project master has sunken into it already cost land Cruiser fresh and continues to pay and pay.
You are not the person for this hire.
And cheap niche you will not be able to compete on price with Pestani.
1. How are things going with the performance compared to benchmark php looked php the go wins in 2 times speed
(maybe I should continue to create sites in php)
One of the most heavily loaded sites in the world made with PHP - Facebook, example.
Technically Go faster. If your server and client parts only 10 meters.
But in the world of web is very large delays is the communication between server and browser, there's a very different distance and a different order of delays. And it is programming language independent.
On their background if you normally have programmed the site should not slow down neither in PHP nor in Go.
2. Does golang for seo optimization-the results
(if frontend not admin panel to take angularjs the entire site will not be indexed)
You with this level of understanding before to solve something.
Do what the elders say.
3. How to choose the bundle for the server maybe a nginx or apache support for golang (or go there is your server and how it in comparison with others)
This is not a language. This is due to the administration, design, architecture of the system, but not language.
4. Does golang mysql and what speed
The speed of DBMS is limited, as a rule, the DBMS is a bottleneck, always.
From a programming language that uses a particular DBMS varies slightly.
5. Perhaps there are good frameworks written in golang to create exactly the sites
Revel, Beego.me, gin and a dozen.
They do not need.
Everything you need is already included in the Golang standard library.
To facilitate the work is to look at frameworks - Gorilla, Martini....
6. If golang generally for small or large sites
The only way to find whether the customer to pay.
Go out more expensive to do than with PHP.
So you just fly with the orders.
Cheap jobs at times more.
Orders are to take - it is necessary to have the more qualified, which, judging by the wording - you still have 7 years to practice programming.
7. Are there any pitfalls when developing
For you, it is important that little information, especially little - Russian.