Monitoring, the prescribing of statins, and eventual bypass (endarterectomy) are most likely in your future, with the latter somewhere near the point where you become more symptomatic (poorer or tunnel vision, weakened reasoning and cognitive skills, transient ischemic attacks [mini-strokes]), but ideally about the time your blockage reaches an estimated 50-60%. Note that the three effects I listed is not exhaustive, and that those effects take place with blockage nearer to 80% or more.

To help put you at ease, my then-87 year old dad needed a hip replacement. The surgeon insisted on multiple assessments to determine if my dad was a good candidate. They found he was 90% blocked in his left carotid and fully blocked, or 100%, in his right carotid. The vascular surgeon, the next person we were referred to, listened to my dad to ensure he was competent, and looked at his overall health, and decided she would take him on as a patient. She told us that she wouldn't dream of touching the blocked artery, but that she would take a vein from my dad's ankle and bypass the almost-blocked one on the left side. She did a great job, he recovered, his cognitive skills improved overnight, and he had his hip job about two months later.
So, the message is, you got caught early, you're not bad, you have a long way to go, and you are probably going to be asked to consider an endarterectomy before too long.