Hey, I wanna put a thru axle fork to my bike and I have the Joytech 100x9mm hub, can I put an adapter to transport this hub in thru axle? My frame support tapered forks but the bearing working with normal fork, not tapered, what I have to change for this upgrade?

You can't put a tapered steerer fork in a frame designed for a straight steerer fork.

My frame( Kona lava dome) is compatible with tapered forks, but the bearings are smaller because the fork that comes is not tapered

moved to Mechanics from Fitting

Seems like you have an adapter race on the fork now. You can get any part of the lower headset that you need to fit a tapered fork. I think going to a bike shop would help a lot in this instance. You can also go look at the Cane Creek website

So are you asking about the fork in the bike, which it sounds like you knew the answer to, or the hub in the fork? If it has a 9mm axle, that doesn't work with thru axles. Joytech is a large company with many types of hubs. It is possible that your hub is the kind that can be adapted from quick release to thru axle by changing the hub end caps with Joytech factory parts. But without knowing what model hub it is or if those end caps are available, no one is going to be able to advise you.

an actual 9mm QR axle front Hub can not be easily converted to a Thru-axle setup.
a pic of your front hub (while NOT mounted on the bike) would help this discussion immensely
you will likely need to either get a Thru-axle hub and lace it to your rim, or get a complete thru-axle wheel assembly, with either choice selected to match the axle size/style of the thru-axle compatible with the fork you select.
Note: Replaced link due to too many blocking ads....

https://wheelbuilder.com/blog/thru-axles-demystified-/

I have the Kona lava dome 2022 model, this is the name of the hub that I found in the website

Ride the bike, enjoy the bike and save up your money for a bike that meets your needs. The only thing I would do to a bike like that is upgrade touch points (pedals, grips and maybe saddle) I can move to my new bike. Coil forks on low initial cost bikes are a good sign of the whole bike being a potentially rideable bike but not one to spend money on upgrades. It might be possible that hub could be converted but more than likely it was a part to help hit a really super low initial price point so all the features are taken out generally.

I don't imagine the OP is up for an argument about whatever an "actual" 9mm axle hub is. The fact of the matter is that many modern hubs have "9mm axle end caps" that can be swapped to various thru axle end caps.

That isn't going to be enough information.

so quit trying to argue.

I'm not. I'm clarifying for the OP that your somewhat misleading post might not apply.

alex.. take a look at the Axle ends of your present front hub... are they smooth, or do they have threads sticking out about 4mm beyond a thin locknut?
threaded means it's not possible to switch to "other endcaps"... smooth means it MAY be possible to swap in some thru-axle type end caps...
you will then need to determine which axle size and style whatever fork you choose will require...

Kona Lava Domes are fun bikes.. i've had two that i rebuilt here... the usually short test rides got extended a bit
there's a emerald green one on Portland CL recently... i just might have to pick it up..
update: the green one got scooped up by some lucky new owner... i should have pulled the trigger sooner... sigh

The hub is probably not convertible to thru axle - if it can be converted you should be able to pull off the end caps to reveal a larger thru hole, but if the axle is threaded at the end it's the wrong type, and you need a new hub (and wheel build) or a new wheel.

Thank you all guys, I send an email in official Kona, they said to me that the hub can't convert to thru axle but the frame is able to get a tapered fork but with new bearing