eng lit to teaching?

should i mention in my statement that im only taking an eng lit course because im planning on taking a teaching course afterwards?
(the plan is to finish my eng lit BA, then go to teacher school, get qualified, and teach english in a secondary school)

No
Firstly it sounds unlikely that you'll enjoy or thrive on an Eng Lit BA if you're not that interested in Eng Lit and secondly your plans will almost certainly change during the next 4 years.

oh, no, i know that ill love eng lit ba, i love the process of analysis, its just that im planning on becoming a teacher because i want to take the eng lit ba, i just didnt know what else to do with a degree in literature.

You don't have to mention your plans at all. Most applicants don't understand the possibilities a degree will open up in 3/4 years time. Putting in specific plans usually just comes across as naïve and doesn't benefit your PS