Bonjour Coca,

Here is the "literal" translation:

parmi lesquels choisir = among which  to choose from -> the relative pronoun "lesquels" refers to the expression "nombreux styles (de yoga)" (= "many styles of yoga)

Prepositions + qui, lequel, laquelle, etc : on what, behind whom, beside which (relative pronouns)

I hope this is helpful.

Bonne journée !