Well, Baptists are an actual denomination, like the Methodists, Lutherans, Assemblies of God, etc. They’re a well-defined organization with founding doctrines and a governing body. “Evangelical,” though, is a descriptive term for a kind of Christian, like “traditionalist,” “Trinitarian,” “pietist,” etc. Roughly, it’s a Christian stance that tends to emphasize the experience of conversion, of missionary activity, of Biblical authority, and of preaching the gospel.
There’s a high overlap between evangelicalism and certain Christian churches–especially the Baptists, traditionally black denominations, most Pentecostal denominations, and many other smaller sects. Evangelicals don’t usually set the tone in Catholicism or in more mainline Protestant denominations, but they’re certainly found there.
Hope this helps.