As stated the complete protein myth is just that and was debunked a long time ago.
Meanwhile ask you dr for complete bloodwork to evaluate current nutrition, especially when pregnant your body demands a lot and status can change over the course of the pregnancy
Nope
Most meal service options will max at like 400-500cal per meal so it would be a lot of cooking and a lot of double or triple portions
Honestly look for catering menus from local restaurants