I will help you any time.
FYI: This Japanese translation is very natural and frequently used in the real world. Another idiom with 力 is
お力添え頂き、ありがとうございます。（おちからぞえいただき）= Thank you for your support.
- 力になる = (lit.) I become a power for you. → I help you.
- 力添え = (lit.) attaching power → support/endorsement