In different contexts, we need to use different words to translate the word “same” from English to Hindi.
In many situations, the emphatic particle ही is used.
आप लोग जिस तरह का खाना खाते हों, हम उसी तरह का खाना नहीं खाते – “We don’t eat the same kind of food that you eat”
क्या तुम वोही सोच रहे हो जो मैं सोच रहा हूं – “Are you thinking the same thing that I’m thinking?”
In other situations, the word एक is used:
ऋचा और प्रीती एक जैसी कमीज़ पहनी हुई हैं – “Richa and Preeti are wearing the same (i.e. similar) shirt”
हम सब एक ही गाड़ी में आये थे – “We all came in the same car”
To mean “same” in the sense of “similar”, एक जैसा/समान can be used. To mean “same” as in “one” or “very same”, एक ही can be used.
हमारा एक ही नाम है – “We have the same name”
You might hear some Indians translating these kinds of phrases very literally, for instance “We came in one car only” (translating “ही” as “only”).