We use How is …? to ask about someone’s general health or about the condition or state of something, or how people experience something:

How’s your mother these days? (How is her general health?)

Oh, she’s fine, thanks.

[talking about an old house]

How are the walls in the kitchen? (What is the condition/state of the walls?)

Well, they need redecorating really.

How’s your new car?

Wonderful. It’s so much easier to drive than the old one.

We use What is … like? to ask for a description of someone or something (e.g. their appearance, their character, their behaviour):

What’s her new house like?

It’s a modern one, quite big, with a nice garden.

What’s your new teacher like?

He’s nice. He’s very good-looking! But he’s quite strict.

We don’t use How is … like? to ask for a description of something:

Have you ever had Korean kimchi?

No. What’s it like?

Well, it’s sort of spicy fermented vegetables, cabbage and things.

Not: How is it like?