Welcome to HCM.
Your symptoms suggest degenerative spine problem. Back stiffness
may be due to age related changes in discs and facet joints and also due to muscle spasm. Leg pains may be due to spinal stenosis
. This needs to be investigated. I would suggest to consult a spine specialist and you may need to get xray and mri spine. For milder problem medicines and physiotherapy
works however if it is causing you significant disability
in day to day life then you may need to treated with spine injection or surgery depending on mri findings. Thanks