When a D&D rule uses the word “can” it means you are able to do the thing

A monk using a monk weapon with Dex is somehow mechanically different from him using a finesse weapon? How?

I’ve got an action and an Action Surge. Can two one action spells be cast on one of my turns?

To tweak a spell or ability, is it balanced to swap damage types?

I wasn’t aware that negative and positive energy are not considered magical. Would you apply the same rules to Negative Energy Flood?

If a magic item casts a concentration spell does the PC have to concentrate on it?