Update CONTRIBUTING.md

Author: Manobal-Singh-Bagady

docs/CONTRIBUTING.md

@@ -1 +1,46 @@
 # Contribution
+
+## How to Start Contribution
+- Fork the repository
+- clone the fork by writing the following command
+
+```git
+git clone https://github.com/<YOUR USERNAME>/Generate-QR-code.git
+```
+
+###### replace \<YOUR USERNAME\> with your profile name of GitHub
+
+- make changes in the fork and push them
+- create a pull request
+
+## Local Setup
+
+- ### After running the `git clone` command:
+```
+cd Generate-QR-code/
+```
+
+- ### To install all the dependencies run:
+
+###### if using `yarn`
+```terminal
+yarn install
+```
+
+###### if using `npm`
+```terminal
+npm install
+```
+
+### To start the server:
+###### if using `yarn`
+```terminal
+yarn start
+```
+
+###### if using `npm`
+```terminal
+npm start
+```
+
+#### The website can be accessed at: [`https://localhost:3000`](https://localhost:3000)