The most common emergencies are the ones to plan for first, simply because they are common.

Bad Weather, Fire, Job/money.

If you start by planning for these, you start to cover less common things.

Going back to the basic basics.
In the worst possible situations
3 minutes without air
3 hours without shelter
3 days without water
3 weeks without food.

Going to take air as a given.

Shelter-
Bad Weather or Job/money usually In place- (except hurricane zones)
This is optimum- most of your stuff is already there.
Ask yourself- How can I make my shelter better/safer? What is greatest risk to shelter?
Not trying to throw money at problems, just covering basics.
If you own, keeping trees trimmed back. Making sure all gutters work.
If you are in a cold area, making sure you have a safe heat source, have good insulation, and blankets/sleeping bags-
I picked up four 4lb bags from goodwill for 3.99 each (they had 7, but 3 were damaged)

Fire- fire Prep-- Thing #1 INSURANCE. Once you survive a fire, this is the prep that give you back your stuff.

Have several smoke alarms, wired and battery. 2 escapes for each room. This can be hard for non-fit people--My in laws are 70ish with arthritis. MAKE SURE YOU CAN USE THE ESCAPES- I had a rope ladder upstairs- which would have done no good as the @#### window jammed (now fixed)...TEST THEM.

Once you get out- do you have a plan on where to stay? Only good thing about most fires is they are very local-mostly just one house/building.
Hotel/tent/RV/car/neighbor/relative? Have stuff stored outside of your primary shelter- even a prepacked suitcase is 100% less sucky than having nothing but your p.j.s... Pack one like you are planning for a long weekend.

WATER- In place- Store water.
I have a 50 gallon in basement- cost 15.00 for barrel (used) from rent all place- Cleaned with bleach, filled from tap.
I have 5-8 gallons in garage 5 - 2 liter frozen in garage freezer (helps even out freezer temps) 2 2 gallon jugs, from store.

Food- not an expert- barely started in this area. working on plans. Wife is Gluten Free- no flour. 6 yr old hates all beans. sigh