Don't sever the public! Sever means something different! :-)
This way is good:
The primary responsibilities of the civil servant lies in serving the public.
To sum up, the basis for all his actions must be the law.
Instead of "sum up," which might be better in a conclusion paragraph, try this:
Most importantly, the basis for...
Here is another one that can be improved:
The appointments for civil servants are held on meritCivil servants are appointed based on merit, ...
This is a good idea:
A public servant should not play into the hands of the elite and become a tool for advancement of their interests. --- I only changed it a little. When you say "the elite" in this sentence, it refers to "the elite people in society." You do not have to write all of that because when you say "the elite" the reader will understand what you mean.
:-) I hope you practice typing these sentences in the correct way. Practice each sentence 10 times, and your brain will remember the correct way. I'm glad you are participating here.