If you can easily handle with terminal, you can run sudo cp -r /path/to/bloom-origin /usr/share/icons
to copy the folder, also, you can use pkexec to replace sudo
for inputing password in a GUI way.
Not easy with command line? you can run the file manager as root and copy the folder as your ways you using before. But I think it would be easier to intergrate run as root
context menu in file manger for beginners.
This post follows a previous publication
https://bbs.deepin.org/post/223230?id=223230&limit=20&offset=0&postId=1731989
how to copy the "bloom-origin" folder as administrator to /usr/share/icons?