You can try Open Targets (https://opentargets.org), and DisGeNet (http://disgenet.org). The data present in DisGeNet is related to genes-diseases and genes-variants associations. Using Open Targets you will find genes-diseases associations, data about metabolic pathways, cancer hallmarks ...
Also, you can try KEGG (https://www.kegg.jp/) and Reactome (https://reactome.org/) too. They have much info concerning metabolic pathways, but you can select only the pathways useful for your research.