くらいなら means "rather than": the first clause names something you find so bad that even the choice in the second clause is better. It follows a verb in the dictionary form. is the same thing.
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I'd rather die than apologise to that person.
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Better to say nothing than to lie.
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I'll walk rather than take a taxi.
The second clause gives the better choice, usually with or ("is still better"), or as a plain statement of what you will do.
くらいなら or より
compares two things evenly. くらいなら rejects the first one: "if it comes to that, I'd sooner…". The alternative is often something you wouldn't want either.
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The train is faster than the bus.
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I'd rather eat nothing than eat food this bad.
Advice to someone else
Aimed at the listener, くらいなら turns into blunt advice or a rebuke.
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If you're going to complain, do it yourself.
、きごう?
If you're going to do it grudgingly, wouldn't it be better to stop?