We've tried quite a few masks - most wouldn't stop a germ if it had to!
I've concluded that a reusable mask with a filter pocket is the way to go. I recently found this mask at a reasonable price. The mask alone is pretty poor, but when adding the 5-layer filter, I hope it's effectiveness is good. The good things about this mask is that it fits me, the nose part stays in place, and it has filter pocket accessible from both ends. These were ordered from https://www.reusablefc.com/
Amazon is a good place for large quantities of the filters - we change them daily.