I bought tickets to Billie Eilish’s show. They are floor tickets and they say row 1 but no seat. Is the floor a first come first serve or will I be at the front?

I am unable to give advice on this question you should call them and ask

I'm quite sure that when you attend this event. Media security that normally is placed upfront will make accommodation for seating, if available. However, if there are seats, or no seat up front, as described in your tickets. You become part of their major event as a front standing crowd hiper to the event which you and your parties have first dibs on being on media and camera exposure. I suggest to simply have a good evening. Enjoy the entertainment rather sitting or standing. Take lots of pictures and be prepared to celebrate this enjoyable event when the cameras come your way. Thus will be a night for you to remember and share with family, friends and love ones along with the rest of the world on social media because your presence alone captured on camera is proof in the pudding. Have fun and enjoy this wonderful and amazing night. It will be magical. Good luck.

I went to a Maverics game, first time there. I can't imagine a bad seat in the building.