To run this Dapp in your browser first download the BlockChainAssignment file and unzip it.Now from terminal first cd into BlockChainAssignment. Now run a command 'npm run dev' a local server will start running on port 3000 the dapp will automatically open in a tab in your web browser You will need metamask to use this dapp change the mainnet to Ropsten Test net .you will also need some test ether.you can get it from https://faucet.metamask.io/ and now put any string in the input form and submit and sign the transaction.