Hi,your burning feet problem according to me not coming from your spine because walking is comfortable for you as compare to siting now remaining other causes
Neuropathy (diabetic,laprosy)
Vascular(stasis of blood circulation)
Which required blood sugar and color doppler of leg to diagnosed it.
Now your neck ,you was operated few year back and now if your neck hearting you during looking up it is because of
spondylosis and if
neck pain not coming down up to arm
physiotherapy is the only treatment for you.
Thanks