Kyoto to Mt Fuij

I would like to go from Kyoto to Mt. Fuji. I plan on staying in Oasumi. The questions I have are what train can I use to get from Kyoto to Oasumi. Also difficult is it to go from Oasumi to Mt Fuji. I see online it says it takes 45min by care but are there public transportation options available (bus, train, etc.)

Japan Guide has information on how to travel from Kyoto to the Fuji Five Lakes area - see https://www.japan-guide.com/e/e6905.html?aFROM=2158_6900. You can get a train from Kyoto to Mishima Station and a bus from there to Kawaguchiko Station.

Have you chosen some accommodation in Oasumi? They should be able to give you advice about how to travel to and from Mt Fuji.

I wonder what place your "Mt. Fuij" refers to.
What is your main purpose?
Climbing the highest mountain in Japan?
Having a nice view of it?

Oasumi is a district of Fujiyoshida City, Yamanashi Prefecture.
Oasumi district extends about 4 kilometers from east to west.
Its west end is geographically near some railway stations of Fujikyuko (also called commonly as Fujikyu).

South next to this district is Oshino Village known for Oshino Hakkai.