Here's the reality:
Most accent resources focus on fixing the way you pronounce consonant and vowel sounds.
While this is helpful if your native language is really different than English, how you say certain sounds is only one part of a natural-sounding accent (and it’s not the most important one).
If you want to be understood by native speakers, you need to speak with the rhythm and music of English.
In other words, you need to master word and sentence stress, emphasize key words, and break your ideas into smaller, digestible chunks.