Turn on watermarks and proofing
Open the gallery, then Settings.
The watermark option burns your logo, or your business name if you have not uploaded a logo, into every preview.
Proofing lets the client favorite photos and leave notes, which is how you find out which shots they actually want without a long email thread.
If you sell a set number of images, use "How many photos should they pick?" to ask the client for exactly that many. It turns a vague ask into a number they can count against.