How to connect iPhone to LG tv??

If your LG TV is AirPlay 2 capable see this --> Use AirPlay to stream video or mirror the screen of your iPhone or iPad - Apple Support

If the TV supports AirPlay, you can AirPlay directly to it.

If not, you could purchase something like an Apple TV 4K set-top-box, or an AirPlay-compatible Roku streaming stick, to plug into one of the HDMI ports on the TV. Then you'd use AirPlay to that device, and the picture would show up on your TV.

There are a lot of apps in the App Store. Just type 'screen mirroring to LG TV' and you’ll see a list.

I used DoCast, works fine for photos, videos, and mirroring

If your TV doesn’t support AirPlay, you might want to think about getting an Apple TV or a Roku, they make screen mirroring much easier.

If you don’t want to use cables, you can also try mirroring apps

It’s a good alternative when AirPlay isn’t available.

[Edited by Moderator]

Then it's not AirPlay 2 compatible. See if maybe LG has an App in the App Store, which will let you mirror your phone through the app.

Maybe your TV is not compatible with Airplay

Check your TV model here https://www.lg.com/us/support/help-library/lg-tv-which-lg-tvs-support-airplay-2--20151097893431

Rarog888 wrote:

My TV model is not included in this list

A Roku stick, as Servant of Cats suggested, might be your best bet.

Rarog888 wrote:

I don't use this often, so I don't want to buy extra devices

Any apps you can recommend?

Did you do as I suggested above and look for an App from LG, which may mirror from your phone to your TV?