I am planning on closing in this area around the toilet and creating a full bathroom. I am very handy and have had experience with plumbing before but not when having to deal with the basement floor. I was wondering if I am able to install drain plumbing above the floor in the layout I've shown with the sink vanity, the shower and the current toilet. The drain coming down in the corner is from the kitchen sink on the first floor. If not possible to do above floor level then how would I go about doing this under the concrete. Thank you all for the help.