I cant add the downloaded music on my apple watch

my apple watch is a se 2nd gen and i downloaded music from the itunes app on pc and synced it with my iphone 8 (im sorry its my old and current phone) and it worked i got music on my iphone but on the apple watch it doesnt work when i try to search music on the apple watch app it is gray and i cant tap on it btw i use family sharing and the apple watch has the same apple id as my phone