"I am at home" could be said as "Estoy en casa". Literally "I am in house". There are a couple of things to note with this. Since you are speaking of a location, you must use the verb "estar", and not the other Spanish verb for "to be", which is "ser". Also, when used as a term for "home", you normally do not use "la".
Estoy en casa.
casa is how you say home in spanish.(for example) Nos vamos a la casa.
Yo no estoy en casa is the best way to say "I am not home" in Spanish.
casa is the way you say home in Spanish. (for example) Nos vamos a la casa.
son casa
You can say 'Ayudo en casa.'
¿Estás en casa?
mi direccion
llévame a casa
Para la casa
Estoy en casa.
Me voy a casa
mi casa es su casa