If you're a very fast walker it could take you only 30 days to walk 630 miles.
But if you walk at an average walking pace you would complete the 630 mile walk in 40 to 60 days and sometimes it may take you as long as 70 days to walk 630 miles.
During a 630 mile walk your legs are probably gonna get really tired and you'll probably want to take a break for a day or so before walking any further.
So factoring in those breaks it will likely take a person 40 to 60 days at least to complete the 630 mile walk.
The faster you walk the faster you'll cover those miles but the slower you walk the slower you'll cover those miles.
But plan for at least 2 months to walk 630 miles.