TMB is 180-200km long with 10 000m elevation rise and drop. People walk it under 2 weeks.
Most critical part is the accomondation. You will need to book ahead all the places you plan to stay. The demand for this trail is very high. You should book at least 4 months ahead.
Place you stay at have a breakfast kit that you can order when making the booking. Since you will rarely pass a store, then you will be dependent on the breakfast kit and occasional restaurant to grab lunch. All accomondations that I stayed in offered dinner.
It is much more of a wilderness hiking adventure than
Camino Frances which has accomondation and restaurants every few kilometers. Also, TMB has the most breathtaking views you can imagine.
Camino Frances you can do without any training. Especially if you start in Pamplona or later. For TMB you will need to train well or you will be in trouble. Especially if the pack weight is too much.