When do you have to use it, but not how?

It is a common word in spoken English.

Almost everyone takes part in the "Best Garden Competition" every year, but Joe wins every time.

Almost everyone signs up for the "Best Garden Competition" every year, but it is Joe who wins every time.

... but usually, most of the journey is spent on narrow, rugged and congested roads.

But along the way, most of the time is often spent on narrow, bumpy and crowded roads ... (usually = very frequently)

This is a beautiful dream, but everything depends on "if".

Sally was amused, but I was embarrassed.

Sally was happy, but I was embarrassed.

(3) How is weaker than but, which does not directly lead to the opposite opinion, so it is often used as parenthesis.

You'll be lucky if he lets you go without a ticket. However, this does not always happen.

If he lets you go without giving you a ticket, you'll be lucky. However, this kind of thing does not always happen.

However, the most surprising thing is that it can land anywhere …

However, the most surprising thing about this plane is that it can land anywhere …

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Simply put: 1. But it is more colloquial than anyway.

2.but must connect sentences directly, while how can connect sentences directly or separate them with commas.

In an argumentative essay, How can be used at the beginning of another point of view.

No matter what he does, he is very clever.

However he did it, he did it wisely.

This book is very expensive; However, it is worthwhile.

This book is very expensive; But it's worth it

This plan leads not to prosperity but to destruction.

This plan brings not prosperity but destruction-