How can I display the results of webform submission in a block and place it on front page?
There are 2 possible approaches to consider, as further explained below ...
Approach 1: using the Charts modules
This is like rolling your own cookies. You create your chart (as you already seem to have done in the image above), using either the &quot;Charts API&quot; (= write some PHP code to populate the charts Array, whereas you put that PHP code in the content of your block) or using the &quot;Views integration of the Charts module&quot; (where you format the Views result as a block).
Disclosure: I'm a (co-)maintainer of the Charts module,
I hope this does not violate the site's policy on self-promotion.
Approach 2: using the typical Webform related charting modules
If you want to create charts from the survey results of the Webform module, there are 2 typical/popular alternatives to pick from:

Webform Charts (used in about 350 sites), to display Webform results in a graphical manner using a charting library.
Webform Chart (used in about 575 sites), which integrates with the &quot;Analysis&quot; tab of a Webform (created with the Webform module) to provide charts for each individual component's analytical data.

The Drupal 7 version of both modules, requires the Charts module (dependency).
Note:
In both approaches you need to decide about which &quot;Charting Library&quot; (= engine) you want to use, either Google charts (easiest setup) or Highcharts (which might require a license also). At any time it should be pretty easy to swap between either library also (that is a key feature of the Charts module also ...).