Yash Raj Films has an official YouTube channel. While they often release old movies for free with ads, Mere Yaar Ki Shaadi Hai is usually listed as a "Rental" movie. You can pay roughly ₹40-₹60 to stream it on YouTube directly—no virus risk, and you can Chromecast it to your TV.
Keep checking JioCinema (which absorbed Voot). Occasionally, YRF movies rotate onto free platforms with ad-support. If it is available there, you can watch it for free legally.
Are you looking for more old Bollywood classics? Let us know in the comments below which movie you want us to find legal links for next.