Yes and no.
It depends what's the current status of your campaign.
If your campaign is approved but you have not proceeded with the payment, then yes. It will be possible for you to change the selected genres, the number of curators that will receive your song, the number of playlists, and the audience size.
Likewise, you will be able to adjust the budget of your campaign if you consider the price is not suitable for you.
This is an image of the "Campaign Reach" section that will allow you to edit your campaign
If you already paid for your campaign then no changes can be done. Nor the genres you selected, nor the song, nor the budget, nor the number of playlists and curators can be edited once the payment is taken.
We always suggest you check in detail if the way your campaign is set up matches with the promotion you want your track to have.