If you are talking to a person that you are familiar with such as a friend, you would say "como estas?" If you are talking to a person that you are unfamiliar with or that you owe respect to, you would say como esta? (without the "s"). You would use the second one with a collegue, or a boss, or a teacher, or an elderly person.
To say 'I have a microwave' in Spanish, you would say 'Tengo una microonda.'
To say 'I have a notebook' in Spanish, you would say 'Tengo un cuaderno.'
To say 'furniture shop' in Spanish, you would say 'muebleria.'
To say 'rich' in Spanish, you would say 'rico.'
To say 'condensation' in Spanish, you would say 'condensación.'
To say 'evaporation' in Spanish, you would say 'evaporación.'
To say 'decompostion' in Spanish, you would say 'descomposición.'
To say 'knives' in Spanish, you would say 'cuchillos.'
You would say "español". It is not normally capitalized.
To say "to skate" in Spanish, you would say "patinar".
To say I am not dark in Spanish, you would say: I ser no oscuro
To say 'cow' in Spanish, you would say 'vaca.'