Usage patterns
みんなで〈動詞〉to do something together, all as a group
Let's all go to the park together tomorrow.
〈物〉をみんな〈動詞〉to use up or finish all of something
I ended up eating the whole cake.
みんなに〈物〉をあげるto give something to everyone
I gave souvenirs to everyone.
みんなが〈動詞〉everyone (all people) does something
Everyone agreed with that opinion.