They are vastly different, in tinkercad you mkstly operate with 3d primitives to make your model end result being an stl file. Freecad supports this workflow as well but their main loop is completely different, you draw your part in one dimension, then extrude it, then draw details in other dimensions and do operations on them, in the end you ideally get an model that can be easily modifable in every step. You can change for example hole diameter in your drawing and it will automatically propagate into model.