Updated README.md file

Updated README.md file to add table of contents but still some content is - - - missing from the author's side such as  Troubleshooting and FAQ missing for common problems faced during project setup and also missing acknowledgment.
- CONTRIBUTING.md file missing
- Code of Conduct added
- Citation file missing

README.md

@@ -1,3 +1,30 @@
+# Table of Contents
+
+- [Table of Contents](#table-of-contents)
+- [Publications](#publications)
+      - [Graph-based Neural Weather Prediction for Limited Area Modeling](#graph-based-neural-weather-prediction-for-limited-area-modeling)
+      - [Probabilistic Weather Forecasting with Hierarchical Graph Neural Networks](#probabilistic-weather-forecasting-with-hierarchical-graph-neural-networks)
+- [Modularity](#modularity)
+- [Installing Neural-LAM](#installing-neural-lam)
+  - [Using `pdm`](#using-pdm)
+  - [Using `pip`](#using-pip)
+- [Using Neural-LAM](#using-neural-lam)
+  - [Data (the `DataStore` and `WeatherDataset` classes)](#data-the-datastore-and-weatherdataset-classes)
+    - [MDP (mllam-data-prep) Datastore - `MDPDatastore`](#mdp-mllam-data-prep-datastore---mdpdatastore)
+    - [NpyFiles MEPS Datastore - `NpyFilesDatastoreMEPS`](#npyfiles-meps-datastore---npyfilesdatastoremeps)
+    - [Graph creation](#graph-creation)
+  - [Weights \& Biases Integration](#weights--biases-integration)
+  - [Train Models](#train-models)
+    - [Graph-LAM](#graph-lam)
+    - [Hi-LAM](#hi-lam)
+    - [Hi-LAM-Parallel](#hi-lam-parallel)
+  - [Evaluate Models](#evaluate-models)
+- [Repository Structure](#repository-structure)
+  - [Format of graph directory](#format-of-graph-directory)
+    - [Mesh hierarchy format](#mesh-hierarchy-format)
+- [Development and Contributing](#development-and-contributing)
+- [Contact](#contact)
+
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