Can someone tell me how to Two-handed tap on my guitar and also explain to me what is augmented chord
Two hand tapping is simply hammering on and pulling off with your picking hand. Try and do the same movement with your picking hand when tapping as you do when hammering on/pulling off with your fretting hand.
An augmented chord is a major chord with an augmented 5th, which is a 5th raised a semitone.
uhhh i guess you two hand tap by playing something normaly, and play something to acompany it with you second hand higher up on fretboard.. best i can explain it.. theres some videos on UG TV that can help
An augmented chord has the formula 1-3-#5.

Example: A C Major chord has the formula 1-3-5. The notes are C-E-G

A C Augmented Chord has a sharpened (augmented) fifth, hence its notes would be C-E-G#

As for two-handed tapping, check out the lessons here on UG. These seem decent: