To share with others, you first have to make a file to share.
Once you have created the file, you can share it with others.
To create a file, open the Google Drive website. On the left side of the screen, click the button that says "New".
Then, a drop down menu will appear, which is where you will select the kind of file you want to create.
If you already have a file created that you want to share, start by opening up that document.
Then, click the button on the top right of the screen that says "share".
This will bring up a screen where you can type in the email of who you want to share the file with and what kind of editing permission they have.
On this screen, you can also copy the link to the file to send.