Would be better if you list what sound bar model and TV model you have so people know what connections you can use. If you can't use HDMI then you need to use whatever outputs the TV has, or connect the source you are using to the soundbar.
If the TV has an optical audio output you can get an optical to 5.1 analog converter. The output is fixed so you have to use the soundbar remote to control volume.
If the TV has an analog audio or headphone output you can connect that to the front input. No surround sound unless the soundbar has a mode for a stereo input.