50yr male multiple spider veins on front of legs below knees also front of thighs slight yellow in upper eyelids is it caused by aging?burping bloated

You are describing: peripheral venous disease which is extremely common in the US as well as worldwide. The "yellow" above the eyelid may be a xanthoma, and your belching and bloated sensation is quite possibly due to air swallowing which is common in smokers. I am giving you an educated guess on the latter two, but you have, at the very least peripheral venous disease the extent of which needs to be determined.