best insoles

Hey strangers I dont know.... Because I want to get fit I wish to do some more walking up around the country side where I live.. so far I attempted a walk today however my feet are now killing me and ache so much so was wondering what the best insoles were for the job? Im not gonna be spending huge bucks on £100 insoles im not that mad .
I guess also that it doesn't matter what shoes you wear if there flat they will hurt and il need some good insoles. Also I dont want to buy amazon ones because I am against amazon and there monopoly over the world and never buy a single item from amazon.

I have looked at a few and one of my friends said he got a pair from ere which have worked for him, dunno if they will be the best or not because I have odd shaped feet  what do you think...

Also can it be that I need to do foot exercises to strengthen my feet and over time my feet become more resilient... kind like playing guitar your finger become stronger and the strings hurt less?

I aim to at least do 2 hours of walking in the mornings from now on!
Help would be really good.
Thank you.