Hello @kimmie99,

Welcome aboard to the Community. I can share some information about the accounts in QuickBooks.

You can still access all inactive accounts through the Chart of Accounts section. To answer your question, yes, you can enable it back by changing the filter first from the small cogwheel icon.

For the detailed steps, here's how:

1. Click the Gear icon in the upper-right corner.
2. Select Chart of accounts.
3. Press the cogwheel icon above the Action column.
4. Put a checkmark beside Include inactive. 
5. Search for the account.
6. Select Make active under the Action column. 

For additional reference, I've attached a link you can use to learn more about how the chart of accounts works: Understand the chart of accounts in QuickBooks.

Drop me a comment below if you have any other questions. I'll be happy to help you some more.