How do I validate my idea?

I am very serious about this one idea and I think it would be very useful for me and my family.

So, I want to ask the founder and the pms here "How can I validate this idea".

I don't want to jump right into creating this product without some validation.

There is a global competitor for this idea, but they have very small download number around 15k downloads across both platform (apple+android).

I have a budget of 5k ruppee to validate this idea.