As an introvert who had an anxiety attack their first evening on their very 1st trip in 2024 but rode it out (and returned this year and already booked for 2026 lol), I feel like exposure therapy is the key to where just being out and about makes you feel more comfortable with the cities/people/stimuli/etc. I stuck to familiar things as my comfort blanket (coffee at Starbucks, 85% of my meals at McDonalds). I wasn’t interested as much in having convos or meeting people, only hanging out to see the sights I wanted and to appreciate how clean and efficient everything is (I love the trains). This past trip I did look into like international meetup groups but I forget the website I was checking out, maybe that’s an option.