Should I Use Will or Would in an If-Clause?, Grammarly
The conditional clause generally does not contain “will", but correct to use them if: 1) the action in the if- or when-conditional clause occurs after the main clause: "If it will cure my pain, I will take the medicine"; and 2) it is a modal verb (willingness, persistence, a wish): I will have a cup of tea if you'll excuse me"
modal verbs（法助動詞）, British Council
