Accounts don't have to be physically "real" with your Bank. That's one of the insights of the "envelope system" that isn't always obvious.

One of the benefits to specifically using a double-entry system (including most of the PTA space) is that it makes it easier to build your "envelopes" as hierarchical sub-accounts. Instead of having just Assets:Checking you could have Assets:Checking:Grocery and Assets:Checking:General and Assets:Checking:Entertainment and so forth. The Assets:Checking sum of all of Assets:Checking:* will still reflect your total checking balance for situations when you need to know that information, but the sub-accounts in your double-entry system become your "envelopes" to check on your budget spending and to transfer between.

Automating your budgets can be just a matter of when you get your Income:Salary transaction you split it appropriately between the various Assets:Checking:* sub-accounts you want. You could automate other transfers between them as necessary as well.

You can also automate things like verifying your Expenses:Grocery account always takes funds from Assets:Checking:Grocery rather than any other "envelope" account when paid for by your debit card. (With Credit Cards potentially needing a different level of automation, and maybe a bunch more Liabilities:* sub-accounts.)

Your bank won't have any idea of those sub-accounts and nothing will physically prevent you from overspending those sub-accounts, of course, but also you can automate warnings for that and you would have visibility of that in your sub-accounts "going negative" when you spend too much from the same envelope.