Invoice/payment dates

[Aldous Everard]

I am new to Gnucash, and a little uncertain of how it works. I have a
few questions,

1. If I send out an invoice, can I enter it as a sale, then when it gets
paid update a field so that it shows up on the bank balance?

2. Can Gnucash account for VAT?  It does not have a seperate column for
this, but I don't want to have to enter VAT as a split payment every
time.  Is it capable of calculating VAT for returns?

Thanks in advance

Aldous