Hi Veronica, In most cases 'I'm learning' translates to 'minä opettelen'. 'I study' is 'minä opiskelen', unless you think of it as 'I do research on'; then it would be 'minä tutkin'.

are they changable appendix according to some verbs ? like opiskelemme or opettelemme

Sorry for the messy format.

Some examples I am studying / learning - Minä opiskelen / opettelen You are studying / learning - Sinä opiskelet / opettelet He/she is studying / learning - Hän opiskelee / opettelee We are studying / learning - Me opiskelemme / opettelemme You are studying / learning - Te opiskelette/ opettelette They are studying / learning - He opiskelevat/opettelevat