Depending
on what you would want to achieve, you can create a new spreadsheet in your Google
sheets or import and already existing blank or old spreadsheet to Google
sheets. To create a new spreadsheet, you will click on the new spreadsheet
option from the Sheets Homepage. Assuming that you already have a G suite
account, from your Google drive, you will click New - Google Sheets - Blank
spreadsheet.
To
import, go to Drive, click New and then file upload. Choose your already
existing spreadsheet from your PC and add it to the drive. While in drive,
right click the spreadsheet you would like to convert and the select open with
Google sheets