Can a doxie be litter trained?

My first doxie was 3 when he rescued me. Last month and age 7 I lost him to cancer. I am now considering getting rescued again by a 9 month old female. I am 60 + with bad knees and live in an apartment. Living on the 3rd floor I’m thinking it will be difficult to get her outside to do her business before an accident happens. I have read of using pee pads but I have also heard about litter training. Also reading about sometimes having difficulty training a doxie I am wondering if I would just be beating my head against a wall. I didn’t have this issue with my male because I was living in a first floor with easy outdoor access..