Yes, if you are intending to return to Windows 7, I would strongly suggest waiting to separate your home and work accounts. Depending on how long you've had Windows 10 installed, the process of downgrading to Windows 7 may require you to restore the computer to factory condition, in which case any changes you make now might be moot!
During the process of moving back to Windows 7, you will "create" one account out of the gate...if you have to do a factory restore, this will be created for you during setup. Otherwise, your current computer account will be brought over. Either way, you will want to determine whether you want this primary account to be used for home or work.
Then, you'll want to create a second account to login to in order to keep you home stuff separate from work (or vice-versa). To do this:
- Open User Accounts. Click the Start button , click Control Panel, click User Accounts and Family Safety, and then click User Accounts.
- Click Manage another account. If you're prompted for an administrator password ***** confirmation, type the password ***** provide confirmation.
- Click Create a new account.
- Type the name you want to give the user account, click an account type, and then click Create Account.
Afterward, your login screen (the screen you see when you first start the computer) will display these two "users" when you boot. Now that you've set up two accounts -- one for home, and one for work -- just click the one you'd like to sign into at any given time. Having these two accounts will keep all of your documents, photos, email, etc. separate.