Great Song!
Standard Tunning.
Good luck with the rhythm. Just listen to it.
The song is actually quite simple, just rhythmically challenging.
1) Intro
[ Tab from: https://www.guitartabs.cc/tabs/j/juanes/la_soledad_tab.html ]
|-----0--------------0---------------------------------------|
|---1---1---1------0---0---0---------3--------------3--------|
|--2-----2---2---0-------0---0-----2---2---2------1---1--1---|
|--------------------------------3-------3---3---2-----2---2-|
|-0------------0---------------0-----------------------------|
|----------------------------------------------0-------------|
1a) Intro Continued... dm - G - C - am - E7/B - E7 - am - A
2) Verses - ||: dm - G - C - am - E7/B - E7 - am - A :||
3) Chorus - ||: am - E7 :||