Read it, all the way through.
There are colored versions you can find.
Interesting. Dragon Ball is quite praised, but it obviously has its fair share of backlash. Well, more than fair. Most criticisms you see are from people that actually haven't consumed the series and think that because Dragon Ball paved the way for other series, that Dragon Ball itself is inferior. This couldn't be further away from the truth. Just read it for yourself and form your own opinion without being influenced from outsiders who have no idea what they're talking about.
Dragon Ball is praised by like so many mangaka. And yeah, it doesn't have that many copies sold without reason. It has the most copies sold per volume of like all time I think? Demon Slayer might be above currently, but you get the point. The anime did help boost manga sales yes, but most people who weren't exposed to Dragon Ball through the manga were inspired to pick it up because of the anime highlighting how good it is. And you're right, without an anime, the first few volumes sold like 2-3 million copies. This was before the anime, and when it was a gag manga instead of like super serious stakes. Even then it was still filled with strong characterization and world building.
It is, and you'll absolutely enjoy it.