26th birthday in Stockholm

Helloo to everyone ✨ My birthday is in the middle April and it will be my first time celebrating in Stockholm! People here plan well beforehand and I'm stressing a bit. I have a friend group of about 10 people and I would love to plan something fun for us to do. I prefer an activity (like karaoke) but if you have any suggestions for a themed party I would love to hear them. Everything I've seen so far is really expensive so if you have ideas on the affordable side I would appreciate it. Thank youuuuuuu💜