Changing the toilet pan and cistern:
Now if you want to change your toilet over to a more modern style or are wanting to move it to another position in the same room or nearby. Can you get under the floor to access the main trunk line serving this existing toilet?
As if you have a concrete floor then look to see if the toilet pan itself is a P-trap going outward's by flowing through the wall. Or is it an S-trap pan flowing outward's through the floor? And sometimes you can strike a turn to the left or to the right P-trap pan called a turn-trunk pan. These all go through the wall or may as an afterthought discharge through a bend through the floor also.
Either way if you have a concrete floor and you wish to change the position of your toilet by an amount left or right see if you can plan it so your new position is still on the outside wall near the drains, and wall pipe work beyond this wall.
If you do wish to relocate this new toilet to a position in towards the middle of the room off the outside wall then know that you will have to cut up the concrete floor and place a new section of 4-inch (100 mm) PVC drain underneath this slab going out and joining into the main sewer drain outside this room under the path or ground thereof with a Y-junction.