Can I use my Personal Hotspot to connect to Smart TV?

If your Smart TV supports Wifi connections, you can connect your Tv to the iPhone's personal Hotspot like you would a normal Wifi network yes.

Note, that streaming apps on the TV, like Youtube, or Netflix will use your iPhones data allowance from your plan, and your carrier may throttle your plan if such things are against its fair use policy.

If you are asking can you create a Personal Hotspot with your iPhone to use as wireless Internet connection to your Vizio TV, the answer is potentially yes. However, the amount of data that will be required for program streaming may quickly deplete your monthly data plan with your cellular provider.

Ref: Share your Internet connection with Personal Hotspot - Apple Support