Insurance after warranty expires on Mac book

I’m not sure what your question is. If you are talking about the 1 year apple warranty, then it is not possible to get more warranty. If you had wanted an extended warranty provided by AppleCare+, it must be purchased within 60 days of purchase of the mac.

An alternative is taking out an insurance policy from a conventional national insurance company(like Allstate, in the USA).

Not exactly sure what you are asking that you need assistance with.

If you purchased an AppleCare+ plan with your MacBook, it extends the basic 1-year warranty that comes with all Macs. If you are asking "Can I get an extension on the AppleCare+ plan?" then the answer is: potentially yes.

Ref: Extend your AppleCare+ coverage - Apple Support