@ajn what version of Gopro do you have. Some have a mini HDMI built in so alls you’d need is a mini HDMI to HDMI lead. Again you can use USB if your current TV allows or SD to USB again if your current TV allows or you can use RCA lead adaptor. RCA 3 inputs that look like microphone plugs – Yellow Video signal Red and White stereo sound.
Rather than going into detail look here…..
https://www.leawo.org/entips/how-to-connect-gopro-to-tv-1410.html