Great try! But "upendo" is a noun meaning "love" and here you need to conjugate the verb "kupenda" meaning "to love": Mimi ninapenda Kiswahili. Na mimi ninapenda Kichina. This sentence can be further shortened, but that will come later :)
"Kijapani anakuja." The Japanese language is coming?
"Halafu nitaanza kujifunza Kijapani." (And (then) I will begin to learn Japanese.)
In Swahili you cannot use the "na" tense even for the near future.