Step by step process:
Export your private key from Electrum Wallet
Go to Blockchain.info
Sign up and after logging in, go to settings. Then in settings, you will see addresses as shown below:
Then click on Import Bitcoin Address as shown:
Then add your private key as it is in the form as shown:
Click import, and you will be able to use your BTC again.
Transfer your BTC from that address/es to any other new address (just to be sure)
Now to get Bitcoin Cash, just go to Settings > General
There you will see a button near this to claim your Bitcoin Cash as well:
After this, there is an option in Blockchain.info itself to sell your BCH for BTC. Or you can send those to any other exchange out there.
Please follow that and let me know if you were able to retrieve the coins.