“有自信心”常见的英文表达是 have confidence in oneself 或 be confident。
have confidence in oneself：强调拥有对自己的一种信任感，侧重内心层面的自信特质。例如：You should have confidence in yourself and believe that you can overcome any difficulties.（你应该对自己有信心，相信你能克服任何困难。）
be confident：更为简洁直接，描述处于自信的状态 。例如：She is always confident when speaking in public.（她在公开场合发言时总是很自信 。）