7zip use AES256 which is very safe.
I first encrypt the wallet within Electrum with a long password, and then use 7zip to encrypt the wallet file with a different long password.
I keep the encrypted file in my offline laptop and an USB as backup.
But when I use 7zip to encrypt the wallet file, I only need to type the password once. After that, everytime I open my file I don't need to type the password. I want to make sure that everytime I open the file, I need to type the password.
Also, when you open electrum, it loads the wallet file instantly right? So how do you encrypt it with a long password? I just have one password for it and no encryption.
Not sure what you mean by that. Every time you want to open/extract the .7z file you need to type the password.
Yup you don't need to type the password to open electrum and see the balance and addresses, but you need to type the password to spend the bitcoin or see the private keys. So, your bitcoin is still safe if someone has your wallet file only but not your password.