You need a stereo audio amplifier between the Pi’s analogue audio out and your speakers.

If you’re ok soldering something like the following should work and could be powered from the Pi’s 5V.

https://www.amazon.in/Solnoi-Electronics-PAM8406-Amplifier-Potentiometer/dp/B07HDP7222/ref=mp_s_a_1_10?keywords=stereo+amplifier+3w&qid=1584776772&sr=8-10