Need to build one session for my website

We are looking to build a .PHP backend of the website and even develop a front end for our website. This will be a set of pages, which users can login, give their reviews, answer all the experiences, share images, and even an opinion for registered people to respond to the comments. So, it will be a user review session that will tag to the different products in that genre that will help them get all the answers. So, a total of 3 pages have to be developed, which will be interconnected to each other.

We will need:
1. UX/UI Designing
2. Complete backend and front end development
3. Timeline and costing for both, we can outsource certain bits if needed