Make API Call to Google Adwords from Php Coded Website

1stly, I would need webpages to make API call to Google Adwords and thus display the monthly search volumes of selected list of keywords, and the individual keywords should have their own monthly search volume displays from a start date to an end date as specified by user on the site page. Common start date and Common end date applied to all the keywords, for simplicity to programmer. Preference is for the list of keywords to be uploaded in csv format. Reason: I don't want to enter each word individually on the webpage, a csv file will contain all the keywords I want monthly search volumes for, and uploaded in a single go. Illustrate to me how to change to my own credentials later to connect to Google Adwords account. Use yours during the development stage. 2ndly, need to find 5-10 related keywords for every keyword in my list. 3rdly, to get their monthly search volumes for each of the related keyword (from point 2 above), over the same reference period, ie start to end period as the main keyword on my csv file. Example, if coca cola main keyword throws up 5-10 related keywords, then each of these too to have their monthly search volume. Start date and End date selected on the webpage. Keyword list uploaded in a csv file by me, for convenience sake. Conditions for payment: Upfront Escrow to be created for only 1st requirement above, and once that is accomplished, only then will I create escrow for 2nd and 3rd requirements above. All 3 escrows released only at the completion of the project, when freelancer reinstates the work on my website for which I provide ftp access to transfer source codes to me, Otherwise, without source codes, I receive nothing, and no escrows will be released. This is to ensure customer's and freelancer's interests are safeguarded and to honour freelancer.com policy where payment is concerned. Please read conditions of payment before placing your bid, thanks for your assessment and attention.