Pil in supreme court/ high court have same power/ jurisdicti

Yes                                     

Answer to your first question is: "It depends". For example, if the Madhya Pradesh High Court has issued a direction to the Madhya Pradesh Government on a particular issue, that will be binding on MP Government only and it will not be binding on other State Governments (for example, Gujarat Government) for a similar issue. On the other hand, if the MP High Court gives a direction to the Central Government, it may generally be binding on it for the whole country though sometimes (depending upon the issue involved, such as an issue of local importance only, say for a particular river in that state) it may be binding even on the Central Government also only for a limited area.

On the other hand, an order of the Supreme Court is generally binding for authorities in the whole country, unless if it is issued only in some local context in the facts and circumstances of the case.

Your question No. 2 is not clear. But, if you mean to ask as to whether the HC can be approached through PIL in respect of a violation of an article of the Constitution, then the answer is "yes".

In continuation of my previous reply, I may further clarify that the powers of the Supreme Court in PIL matters are generally contained in Article 32 of the Constitution (though sometimes, in a given case, powers under Article 142 may also be available to do complete justice in that case). Article 32 can be used only for PILs that involve issues relating to violation of fundamental rights guaranteed under the Constitution.

On the other hand, powers of the High Court in PIL matters are contained in Article 226 of the Constitution, which can be exercised not only for the issues relating to violation of fundamental rights but also “for any other purpose”. That way, PILs in High Court can also be on other broader issues, other than the fundamental rights.

very well elaborated by Mr Aggarwal although query is vague.