upgrade my existing website with new feature

my site in maintenance site name : [login to view URL] drupal version of site is 8.5.4 i need to add new feature to my site: 1- pdf viewer a- can read file from internal url, external url and google drive b- compatible with PC and Mobile c- flip appearance look at this example here : [login to view URL] and here : [login to view URL] d- the viewer contains alternative link for same file. if major url is broken, the second url is worked e- viewer will only built on html5 2- site search a- can search in doc, pdf and page sites, high speed over 30 GiGa bytes using elastic b- search in internal link and external link 3- new theme for my site theme link: [login to view URL] a- customization of new theme and change it to be compatible with my site b- add social website like : telegram c- multi language theme 4- report system for user 5- create 4 pages a- about us b- contact us c- denotation d- Faq 6- text editor a- accept ARABIC TATWEEL b- poetry style 7- message system between user 8- social media properties for site a- like button b- dislike button c- comment d- follow or (subscribe ) Subscription process where user can subscribe the page and when ever anything new happen to the page like add new book update, then all the user get notification to their control panel who follow this page . 9- User permissions: there is many users level: a- user can browse the site and used social media properties b- user can upload the files and create new post c- user can prove new files and new post 10- Auto tag to special word like this example : [login to view URL] 11- sound player a- can read file from internal url, external url and google drive b- compatible with PC and Mobile c- the viewer contains alternative link for same file. if major url is broken, the second url is worked d- player will only built on html5 e- support file list 13- video player a- can read file from internal url, external url and google drive b- compatible with PC and Mobile c- the viewer contains alternative link for same file. if major url is broken, the second url is worked d- player will only built on html5 e- support video quality and translation. example is here: [login to view URL] 14- file uploader a- support upload files to sites remotely from direct links from external sites or locally b- upload files and check if there is same files in site 15- Multiple languages of site 1- arabic 2- english 3- language file can be exported to csv file or txt file then translate it and add new language with easy way 17- add, modify and delete some items form existing list 18- add calendar systems: a- hijri calendar b- Gregorian calendar 19- filters and search box for some pages 20- Counter for some pages as number of material and counter for all visit and download for this page 21- Create new pages for video player and audio player and design it 22- add new section in book creation to add some design card