@jhl
Follow the below steps to create a password for 7zip files. Below pictures will help you in this regard.
1. Right click on the files or folder you wish to compress and encrypt

2. Firstly change the Archive format to Zip (or use 7z if both you and your intended recipient use 7zip), then change the encryption method to the robust AES-256, thirdly enter your password. Then click OK. The rest of the options can be left as default.

Regards,
Siva
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