“申请了很多小号”可以翻译为：
"I created multiple secondary/alt accounts"
或更口语化："I made a bunch of alt accounts"

根据语境灵活调整：

如果是网络平台备用账号（比如社交平台、游戏）：
"I set up a lot of secondary accounts"
若强调“备用”而非具体用途：
"I registered several alternate accounts"
如果需要保持中立或带调侃语气，也可以说：
"Oops, seems like I have way too many alts now..." 😉