Why do journals require authors to provide funding information? Recently I have communicated a manuscript to Springer journal. In editorial system I was required to furnish funding information. If the funding information is available then does that mean that I have to publish my work through open access by paying fee from funds that have been sanctioned  to me?

Although the journal is not open access journal but I am afraid if they ask for article processing fee after acceptance of manuscript. My sanctioned funds does not cover article processing charges
Funding information is often required even when a journal has no open source option to it. The source of funding is a major potential conflict of interest, and as such is a key piece of information in evaluating a paper.

That being said, it may also be used to determine things like whether or not they should give a break on open access fees, whether it needs to be deposited in Pubmed Central, etc.