If we upgrade to Quickbooks Plus will we lose the information we already have?

No, you won't lose your data when upgrading your QuickBooks Online (QBO) plan, Paulo. I'll provide further details about this and help you complete this task.

Since you need more stock control, upgrading to the QuickBooks Plus edition would be a wise choice. With its Inventory feature, you can efficiently track your inventory levels. To do so, here's how:

1. Sign in to QuickBooks Online as a primary or company admin.
2. Go to Settings or the Gear icon and select Subscriptions and billing.
3. Make sure your payment info is up to date.
4. In the QuickBooks Online section, select Upgrade your plan.
5. In the Plus plan section, select Choose plan. 
6. Follow the on-screen steps to upgrade your plan.

Once you're done, set up and track your inventory in QBO.

I've got you covered if you have other account management concerns or questions about inventory tracking in QBO. Drop your comment below, and I'll gladly help.