Can you get adaptors or something if they have sealed bearings? Are these adaptors easy to get? Are they expensive?I‘m very unsure of all of this so please explain.
Short answer? No. Long answer? Through-axle hubs are designed so that the axle slides through roller bearings and locks into the fork while maintaining the correct spacing. The hub shell is often much more heavily built and the axles are larger diameter. A regular hub cannot achieve this. One cannot use a regular hub on a through-axle fork either, but it might be interesting to try and machine some gizmo that might (or might not) work. This would certainly cost more than a wheel with a through-axle hub, and the standard hub would never take the abuse the through-axle version could.
No, you must get another hub, and usually they're like $65+
