@LiquidSnake You should be able to make the background white via the Tools in snapseed. See more here https://www.techjunkie.com/make-background-black-white-snapseed/
May wish to look at this tutorial for a guide to the features in Snapseed https://www.mobiography.net/apps/snapseed-app-tutorial/
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
My Device- S21 Ultra 5G ( SM-998B/DS ) CSC= BTU , 12GB/256GB
One Ui 5.0,Android 13 .
Bgeraser.com is also a good choice which not only allows you to remove the original background from image but also allows you to delete any unwanted things in a photo, such as a tree, a car, a person, etc. This tools is also free for use,