Hello Cameron222,
Here's my answer. In order to achieve this, first create a Standard Web-to-lead form, and then on step 8 of 9: Edit Field Description, look for the formulas for Customer-Contact. Copy the formula and you can use this formula for populating First name and last name in your desired field. In the last line of the formula after if statement, switch the FirstName with LastName and vice versa. This will populate Last name followed by space and then the first name.
Also, you can set the default value for Opportunity Close Date to current date by using this formula NOW()
I hope this helps!
-Inder