Step 1: Make sure 7-Zip is installed on your machine.
Step 2: Right click on the file or folder containing the items you wish to compress, then hover your cursor over the 7-Zip option and select add to archive…
Step 3: You will be met with a menu where you may change the parameters for your compressed file. On this menu you should select the 7z archive format leaving most other options unchanged.
Step 4: Move on to the Encryption settings, here you can set a password to use for your file. Make sure the password is secure and memorable/recorded as the compressed file will become inaccessible otherwise.
Step 5: Select the AES-256 encryption method and tick the Encrypt file names box.
Step 6:Once you have selected OK 7-Zip will begin to compress your file. How long this process takes depends on the size of the file and level of compression. If this process is going to take an extended period you may select the background option and continue to work.