Is it possible to restore only with WIF?
Yes, this is possible.
But if you further want to keep your bitcoins, you should do what LoyceV suggested and first create a new wallet. Then move your funds from your old address to your new wallet (sweeping).
If you don't want to further keep your coins, but just want to send them to an exchange or something like that, simply importing the private key will work. You don't need to create a new wallet/seed in this case.
When downloading/installing electrum, make sure you do verify the signature AND that your PC is clean. Also, if you are creating a wallet, make sure to backup your seed (only offline! - NOT on your computer).
