Question

What is the scientist's next step, if he concludes that his hypothesis is false??? help please

Answer 1

hypothesis is false then he should prove it by proper experiments and should try to build new hypothesis based on where he did mistake

Answer 2

Finish their experiment and conclusions, then remake their observations and reform a new hypothesis and procedure, and repeat until they are correct.
Often times, in classes especially, the hypothesis formed is the complete opposite and it is easy to tell from the experiment what the correct hypothesis is, in which case you normally just address it in the conclusion and state that your hypothesis is false and why.