Rex wants to run a Saturday race. Every plan he makes starts with if.
Two halves
A conditional has two parts. If names the condition. The other half is the result.
If it rains, we stay in.
If I train, I feel ready.
If she calls, I will answer.
If I were faster, I would win.
The race weekend
The tense is not decoration. It tells you which picture you mean: a fact, a real future, a dream about now, or a regret about the past.
Putting will in every half is the first slip. We will not do that.