methods and devices in measuring dew point, direction,humidity, pressure, moisture, pressure?

Answer 1

Dewpoint meter for dewpoint, Hygrometer for humidity, pressure gauge for pressure..

Answer 2

A mercury barometer for pressure. A dry bulb thermometer for temperature (just an ordinary thermometer) and a wet bulb thermometer for humidity and dew point. This is an ordinary thermometer with a thin piece of cloth wrapped around the bulb, dipping into a water container, so the cloth is kept damp. You'll need tables, which you can download from the Internet, to convert the wet and dry bulb readings into relative humidity and dewpoint. And a weather vane, which you can make yourself, for wind direction.