What's wrong with this sentence? "If I can go, I would." 

"Can" should be "could," since this is a second conditional.

If I had slept better last night, I'd be more awake right now.

If I had slept better last night, I would have been more awake at breakfast this morning.

If I slept better, I would be a better pilot.

What do the two "I'd"'s mean in the sentence "If I'd known you'd come today, I'd have baked a cake"?

"If I had known more about chemicals, I would not have destroyed my laboratory." Which statements are true?

The laboratory was destroyed, and the speaker didn't know enough about chemistry.

The laboratory was not destroyed, and the speaker didn't know enough about chemistry

The laboratory was not destroyed, and the speaker did know enough about chemistry

Had I known it would rain, I would have brought an umbrella.

Were he taller, he would be a basketball player.

If you had been here on time, we would not have missed the train. 

If I would go to the store, I would buy some oat milk.