A Dictionary might give you a few.
List of 4 letter words that start with the letter "K"KneeKnowKeenKilnKeepKingKnitKiteKeel
List of 9 letter words that start with the letter "K"KnowledgeKnighting
I'll list some for you below:cablegramcalfskincallbackcampfirecampgroundcandlelightcandlepowercandlestickcapsizecarpetbagcarpetbaggercardboardcareworncarloadcarportcatbirdcatboatcatchallcatnapcatnipcattailcatlikecatwalkcavemanchalkboardcheeseclothcheckerboardcheckmatecheckbookcheerleadercheckpointcheckoutcheckupcheekbonechestnutchessmanchildbearingchildhoodchildlikechildbirthchildproofcitizenshipcitywideclapboardclearinghouseclubhouseclubfootclothespinclotheslineclockwiseclockworkcockfightcobwebcoachmancocktailcoffeehousecoffeepotcockpitcockroachcoffeemakercogwheelcollarbonecolorfastcomedowncookwarecookbookcopycatcopyrightcornmealcornerstonecoastlinecouncilmancourtroomcourtyardcourthousecrackerjackcowbellcowhidecrabgrasscraftsmancraftspeoplecrestfallencrosswordcrosswalkcutawaycustomhousecutbackcutthroat
There are no such words.
abridgedaccentedacquiredaddictedadorableaffectedalacrityamateursanointedansweredapproachapprisedappealedarrivingassumingattitudeautomateavailingavoiding
faithfancyfadedfaultfelonfencefeastfiendfifthfiredfiberfilthfinchfirstfloatflossfloorfleetflingflaskflashflickflackflirtflintfliesflankflamefluteflushfloodfoundforthfriskframefreshFrenchfrozefriedfrockfrillfrontfruitfreedfunkyfunnyfurry
magpie
MakeMindMostMealMustMoldMileMineMoleMuleManyMastmeatMeetMinkMend
If what you want is a list of words using the letter Q you could go with a Scrabble word finder. That will show words that start with Q as well as words that contain the letter Q.
Some four letter words that start with U are:uglyulnaundountouponureaurgeused
DropDoorDoleDoteDeepDeerDopeDampDankDoneDuneDentdeskDarkDirtDeed
wantwarpwagewaitwadewarmwarnwashwearwhenwhatwhamwhimwaveweekweakweldweepweltwartweedweanwithwinewirewidewiskwishwoolwoodwormwolfwalkwestwaspwiltwake