The best way to read

As my vision has deteriorated, I have become dependent on a tablet reader. I fell into using a fire tablet when my brother sent me one when my arthritis prevented handling or turning pages in paper books. That problem is under control but the poor selection of available large print books means I need to be able to adjust font size. That nine year old tablet is failing. I'm torn between an e-reader and a new cheap tablet. If you've used either, or preferably both, which do you find better? Why?