Trip from London to Stonehenge?

Hi my English Peeps!

I will be visiting the UK in the coming weeks, and would love some suggestions on the best route from London Euston to Stonehenge. Ideally I would prefer the train as I have never drove in Europe/UK, so not as comfortable driving.

Also, would Bath be doable on the same day as visiting Stonehenge? This would be a day trip to Stonehenge and wanted to utilize my limited time in the UK!

Would love to hear all your suggestions and thoughts on the day trip.

Cheers!