Help, after the macOs instalation this popped up, what can i do? (trying to install macOS Sonoma)

https://preview.redd.it/b7j928ihausc1.png?width=1024&format=png&auto=webp&s=3e71eec96941c015bbf17200c41c3924cc180aa0

after clicking ok it tells me to select a startup disk, but none show up & the update assistant does nothing