Bone Heat Weighting: failed to find solution for one or more bones

No problem Erick. Thank you so much for your time. Now may i ask what should i do to correct all of these mistakes? Also i followed this tutorial from scratch.

But its an outdated tutorial that doesnt explain things too much. I had so much trouble creating this. What can i do to correct all of these mistakes? Should i recreate the armature or the whole mesh?
(and if i chose to recreate the model what should i be aware of?)

@paulhart2 Are there any modifiers that can correct the problems Erick mentioned? I am a new guy so could you suggest me some modifiers so i dont mess up again?