Good morning, Diane. Welcome to ecf! I'm hoping you feel like your question was answered. As you can see, there are lots of folks on ecf - and wherever there are lots of folks, there are lots of opinions!
Just in case, here's my two cents. High wattage mods are best for low ohm, direct lung vaping. Higher wattage and lower ohms yields bigger clouds. Lower wattage and higher ohms (usually) equals smaller clouds and more flavor. Most folks who are MTL (mouth to lung) vapers are what we call "flavor chasers." This is not to say that you can't get good flavor at high wattage, but rather that our mouth, not our lungs, is where we taste - so direct lung hits tend not to result in as much flavor.
You can use a coil at wattages below what is recommended. You won't get the most out of that coil, but you can do it. You shouldn't use a coil at wattages higher than is recommended.
Hope this helps!