Is it normal to not wear underwear to bed?
Yep.Totally normal
Yes, it’s completely normal to sleep without underwear. Plenty of people do it because it feels more comfortable or less restrictive.
There’s no rule that says you need underwear in bed. Some people prefer the extra airflow or just find it comfier; others like wearing pajamas or underwear to sleep. It’s mostly a matter of preference and what helps you rest.