Install analytics code, remarketing code, facebook pixel.

I need to install various codes into the body tags of the website.

Codes in include google analytics, adsense, facebook pixel, adroll and more.

Here is an eample of the work that needs to be done:

https://help.adroll.com/hc/en-us/articles/360040116252-Connect-AdRoll-to-your-site-by-installing-the-AdRoll-Pixel

I want to pay a fixed fee for these tasks, or hourly rate that is agreeable for these tasks.

Also, i want users who visit the website on their mobile device to be prompted with a message asking them to add 'website to home screen', if you can do this please let me know, and what type of work is involved for this, thank you.

The website is a PHP script. Please ask me for the website and i can send it in a private message, thank you.