Research Objective is to design online algorithms for graph filter design over expanding graphs under conditions of known and unknown connectivity. The data-sets used in this paper are available online. Code for generating synthetic data is included. In the folder Recsys_new, the experimental setup and online algorithms for movie rating prediction for Movielens100k is provided. In the folder Stochastic_Synthetic_New, the experimental setup and online algorithms for signal interpolation for synthetic expanding graphs is included. In Stochastic_covid, the code for Covid case count prediction over a growing city network is provided.