In the first sentences, the "if" actually means "when" or "whenever" as this is always true. Therefore we need present simple twice.
The golden rules are:
1) if + present tense -> simple (will) future + infinitive for FUTURE SITUATIONS
(= THIS CAN STILL HAPPEN or COME TRUE)
2) if + past tense -> would + infinitive for PRESENT SITUATIONS
(= THIS IS UNREALISTIC NOW)
3) if + past perfect -> would have + past participle for PAST SITUATIONS
(= CAUSE AND EFFECT ARE BOTH ALREADY OVER. NO CHANGE IS POSSIBLE)
4) if + past perfect -> would + infinitive for MIXED SITUATIONS when the cause is in the PAST and the effect is visible NOW.
Here's another example: "If I had known that there is a concert tonight, I wouldn't be here now."
= The speaker didn't know about the concert and it's too late to buy tickets or he has different plans. He, therefore, cannot go NOW. I.e. the cause is in the past (his lack of knowledge) and the effect is visible now. He is wh