Custom homepage designing

[devwaleed]

Hi there, I am an experienced PHP developer but new to phpbb development.

One of my clients has asked me to design a new homepage for his website which is running phpbb v3.x. I have designed the page, it contains PHP scripts as well and regular HTML/CSS design. I want to upload it to its website but I see its not that simple. Can someone guide me to setup a custom homepage with my design on his website.

His domain is like this:

www.website.com - This shows the current homepage which we need to replace
www.website.com/index.php - This shows the forum's index where all blogs are listed.

He is using prosilver_se style and bb3portal for current homepage.

Thank you