Tokyo-Hakone-Kyoto in one day?

Hello to all...Thank you for the help you guys are providing it is really appreciated!!
Our plan is to possibly spend 1 day in the Hakone area and finally arrive in Kyoto.
April 16th leaving Tokyo arriving in Hakone-Yumoto 830am, leaving 2 medium luggages at train station (help here please?) sightseeing the area (which are the must see places and a spot with nice views of Mt Fuji?) returning to Hakone-Yumoto to get our luggages and catch bullet train for Tokyo at around 1630.
Is this a doable plan?
Thank you very much
David

Yes, this is doable. There are lockers and luggage storage counter inside Hakone-Yumoto Station. Coin lockers are found in multiple places inside and around the station (300-500 yen per locker), while the counter is located just outside the ticket gates (350 yen for small pieces of luggage; 500 yen for large pieces of luggage).

sightseeing the area (which are the must see places and a spot with nice views of Mt Fuji?)

You have enough time to do the Hakone Round Course by purchasing the Hakone Free Pass. I'd do the whole loop. We enjoyed the walk up Owakudani, don't forget to eat some of the black eggs!

If the weather is good you can see Mt Fuji from Owakudani, on the ropeway ride on the way down to Togendai, from the Pirate Ships on the way to Hakone-Machi, and from the shores of Hakone-Machi and on the walk to Moto-Hakone, before you catch the bus back to Hakone-Yumoto station.

to Hakone-Yumoto to get our luggages and catch bullet train for Tokyo at around 1630.

I assume you mean Kyoto???

Will you have a JR Pass? If so, then there are no Hikari trains in the afternoon, so if you catch the 4:08pm train from Hakone-Yumoto to Odawara then you can catch the 4:37pm Kodama Shinkansen which takes three hours and arrives at 7:38pm.

If you miss the 4:08pm train you won't get to Kyoto until 8:58pm at the earliest.

Enjoy your trip!

Yes we are going to Kyoto where we will spend 4 nights, after that we are going to Shibu onsen for 2 nights where we will stay in a Ryokan (can't wait!!!).
We are activating the Jr pass on the 16th for a 7 days pass.
Can i purchase a Hakone pass in Tokyo or when we arrive in Hakone?
It sounds like the best way would be to take the train at 1608 for Kyoto instead then later...
Thank you very much for your help!
David

Can i purchase a Hakone pass in Tokyo or when we arrive in Hakone?

You should buy one at Odawara Station.