Code custom product page template for Shopify

I need a custom product page template coded for my shopify website.

I have a model already in mind and would like to be able to create a product page with sections, headings and certain specific details that need to appear on that page the way I want.

I already have a shopify theme, so the template would probably need to be coded from scratch and we would use that template instead of the existing theme's template.

We also need the product layout to be mobile friendly. Looking for people with trackrecord/experience to show.

Thank you