For anyone converting from lastpass to bitwarden there are easy steps to import all your information. I don't think I have to say this but just in case, only do this on a computer you trust. IE: Not a public computer.
First setup a bitwarden account.
Go to
https://Lastpass.com and login
In the gray bar on the left select "Advanced Options" near the bottom.
In the white menu that springs out from that under "Manage Your Vault" select "Export" and Login again with the prompt that comes up.
You will be displayed a wall of unencrypted login info. It'll be a wall of text. Copy EVERYTHING!
Next come here
https://vault.bitwarden.com/#/ and login with your newly created account.
In the blue banner up top click on "Tools"
After the new page loads click on "Import Data" on the left under the "Tools" section.
In the drop down box select LastPass (CSV)
In the bottom box paste all of the stuff you copied from Lastpass and click the "Import Data" button.
Note: (Alternatively you can paste all the login info from lastpass into a text document but make sure to change the extension from .txt to .csv and import it into bitwarden in the final step as a file.) Personally I've found that just copy and pasting into the bitwarden field to be faster.
With this all of your login information should have been ported from Lastpass to bitwarden and ready to go.
Personally I recommend one thing. Since bitwarden is free across multiple devices I recommend letting bitwarden generate passwords for your various accounts and saving them in bitwarden. If you ever need to log into a site on your phone bitwarden will still have access to those passwords there.