Help post: Running smart contract in a private Ethereum blockchain built with Geth from Remix IDE

Hello everyone. I was trying to build a Dapp in my private Ethereum blockchain which I built with a couple of nodes using Geth. Now my problem begins with trying to run the smart contract which I wrote using Remix IDE in the blockchain using "External HTTP Provider". Every time I try to run the smart contract in the blockchain it shows Error and tells me to check the provider plug-ins.
I tried the plug-ins from the official remix documentation but can't get the hang of it. I think there's something to do with –dev plug-in. But whenever I try to set the "–dev console" plug-in it says blockchain failed to unlock the development account. how can I set these things up? Thanks in advance.