I'm planning to hand in my notice soon. Normaly, I'd approach my boss, ask for a chat and then explain in person my circumstances and discuss ways forward. However, we now operate on a hybrid-remote basis, where I can't really expect my boss to be in unless we pre-arrange it.
It kinda feels like a break-up, in that doing it remotely feels wrong. This is probably because the company is small so my leaving is likely to have quite a high impact and our bosses always tried to aim for quite a personal contact with us. They probably don't expect I'm about to leave.
I don't think just waiting until we happen to be in the office physically at the same time is an option as time is paramount. So realistically, I can ask my boss for a video meeting, or I can ask them when they'd expect to be in the office for an in-person meeting. The former feels a little inappropriate in how informal it is. The latter feels like it's kinda "telling without telling" and also feels weird.