Hi there. So I was building an app in which the user will connect to a wifi clock using a barcode.
Basically, the user has to scan a barcode or QR code and the app will convert the QR into a text and search for the entry for the text like, the text is "abc" and the app will get this text using qr scan and will search for the entry or other related data to this text. How can i do so? As a newbie i don't know much about MIT app inventor so please help me out.
You can learn.
Here are some resources to help you learn to use the AI2 tools. A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook App Inventor 2 Book: Create Your Own Android Apps ... the links are at the bottom of the Web page. The book 'teaches' users how to program with AI2 blocks.
There is a free programming course here Course In A Box and the aia files for the projects in the book are here: App Inventor 2 Book: Create Your Own Android Apps
How to do a lot of basic things with App Inventor are described here: How do you...? .
Also look here App inventor español. Offline. Tutorial. Ejemplos. Instalación. Códigos. Juegos. Curso gratis de App inventor. and here http://www.imagnity.com/tutorial-index/ for more tutorials
Learn about components Component Reference
and visit the Library The MIT App Inventor Library: Documentation & Support Help>Library on the MENU
For your Project you can look up the documentation for
- BarcodeScanner for reading QR code
- ListViewer for listing the files stored in a spreadsheet or in a TinyDB The Imagnity link above will provide advice regarding Lists (see
List Blocks On App InventorImagnity.com List Tutorial, Mirrored - @SajList Sorting On App InventorShuffle Lists & Unique Random Numbers
- TinyDB regarding how on works
- etc.
What have you tried Michel? Your Project is doable. 
Learn to do one thing at a time; then put all you learned together is a great strategy.