Why are fewer English people going to their local pubs for a drink? Are they aware that many pubs are shutting down due to lack of customers?

They need to offer either food of a quality you can’t get at home (true gastro-pub experience) or alternative entertainments - live music, poker nights, sports viewing etc.

A range of alcoholic drinks

The pubs with the best chance of survival long-term recognize that they can’t just get away with the same 3 beers, ropey wine and pub-grub. Why pay more for something worse than you can get at home for less?

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You can get takeaway or even cook yourself a wider range of food of good quality

Entertainment (pre TV and radio)

You have 1001 sources of entertainment on TV and the Internet

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You can get a wider range of quality drinks at lower prices from a supermarket

Back in the day (early 20th century and before) the English pub offered things you couldn’t get in a working-class home:

You have to understand what the attraction of the English pub was in the first place.

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Comfortable seating in a warm, cozy environment, or a nice pub garden

But now:

Your home has more comfortable seating and a garden

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In the mid to late 20th century they added food, without the inconvenience of cooking it or washing up.