To say 'I practice sports' in Spanish, you would say ' Hago deporte'
practicar
¿Puedo practicar español?
deporte favorito
la practica
"A team sport" is "Un deporte de equipo."
You can say "voy a practicar".
"Prometo practicar mi espanol"
No lo practico.
It means "swimming," referring to the sport/practice itself, not the verb.
Translation: Actividades de deportes
mi favorita desporte es...