Any coop opening,
(well, except the pop door, but it should have a locked door),
should be securely covered with 1/2" hardware cloth...
.....to keep sparrows out, and predators too.
Ventilation is best if it is adjustable.....top hinged windows are my favorite because they can be left open and keep out most the weather.
Baffles can be good too, corrugated cardboard works well tacked up inside to redirect airflow away from roost in winter.
But it depends on your coop, site, climate, etc.
That's why a pic of your coop was asked for.
Even that won't totally tell the tale tho.
Make things adjustable then get into coop during high winds and evaluate what is working and what is causing problems then adjust as necessary.