If you want to backup all stored passwords from chrome. Do the following

1. Go to chrome://settings/passwords on chrome
2.  Click on the 3 dots above your saved passwords.
3. when clicked an option for exporting password will show up. click on it
4. when clicked you will get a warning that Your passwords will be visible to anyone who can see the exported file. Cancel or Export password??
5. To export your password to computer click export passwords. you will be asked to provide your computer password.
6. your passwords will be exported as a .csv file. save the file to wherever you want on your computer.

Make sure you keep the file safe.