My dog rests his head on my lap while I eat, is that begging

A relaxed head resting on your lap with soft eyes and no fixed attention on your plate specifically is more likely simple affection or comfort seeking, similar to how the same dog might rest a head on your lap on the sofa with no food anywhere nearby.

A head resting on the lap combined with eyes locked on your plate, or a pattern where the head resting only happens during meals and never at other times, suggests food is at least part of the motivation, even if affection plays a role too.

Since either interpretation involves a dog close to your food, the same consistent no table feeding rule applies regardless of the underlying motivation, gently guiding the dog to a nearby settled spot instead if the behavior is unwanted during meals.

If the head resting genuinely seems to be about affection rather than food, redirecting the dog to sit or lie beside your chair, rather than with its head directly on your lap or plate area, lets the dog stay close and get the contact it seems to want without the same risk of accidental scrap sharing that a head right at plate level creates. A hand rested calmly on the dog's back or head while it settles in that adjusted position can maintain the same connection the dog seems to be seeking, just from a slightly different, more mealtime appropriate physical arrangement.