From what car did Bugatti take all the brake parts ? Like the little chains and sprockets and other parts . Looking at this parts , this parts are not specially made for the Royale ..

Although Bugatti usually used as many existing parts as possible on later cars this did not really workout in case of the T41 for obvious reasons.
Only the brakeshoe return springs, the brake lever cotterpins and the chain guide and shield on top of the kingpin have T30 part numbers. All other parts are T41 specific.
Bugwrench

which cars are the closest to the 41 with maybe the same brake parts? when I look inside the C frame , these components are not made for the 41 . Anybody can show how it looks in other big Bugatti cars ?

None of the brake mech on a royale is used on other models apart from the chain and a few fittings from a Type 30 and 35. the Type 46/50 bears looks vaguely similar but no parts are common.