Code from my 3. Onset Scripting Tutorial

client.lua

AddEvent("OnKeyPress", function(key)
    if key ~= "U" then
        return
    end
    local vehicles = GetStreamedVehicles()
    local closest = nil
    local dist = 100000
    local pX, pY, pZ = GetPlayerLocation()
    for i=1,#vehicles do
        local vX, vY, vZ = GetVehicleLocation(vehicles[i])
        local d = GetDistance3D(pX, pY, pZ, vX, vY, vZ)
        if d < dist then
            closest = vehicles[i]
            dist = d
        end
    end
    if closest == nil then
        return
    end
    if dist > 400 then
        return
    end
    CallRemoteEvent("LockVehicle", closest)
end)

AddEvent("OnPlayerStartEnterVehicle", function(vehicle)
    local state = GetVehiclePropertyValue(vehicle, "locked")
    return not state
end)

package.json

{
    "author": "Youtube",
    "version": "1.0",
    "server_scripts": [
        "server.lua"
    ],
    "client_scripts": [
        "client.lua"
    ],
    "files": [

    ]
}

server.lua

AddEvent("OnPlayerJoin", function(player)
    SetPlayerSpawnLocation(player, 125773, 80246, 1645, 90)
    AddPlayerChat(player, "Welcome, "..GetPlayerName(player).."!")
end)

print("Tutorial script has been loaded!")

AddCommand("spawnv", function(player, model, owner)
    local x, y, z = GetPlayerLocation(player)
    local vehicle = CreateVehicle(model, x, y, z, GetPlayerHeading(player))
    SetPlayerInVehicle(player, vehicle)
    SetVehiclePropertyValue(vehicle, "owner", tonumber(owner))
    SetVehiclePropertyValue(vehicle, "locked", false, true)
end)

AddRemoteEvent("LockVehicle", function(player, vehicle)
    local state = GetVehiclePropertyValue(vehicle, "locked")
    local owner = GetVehiclePropertyValue(vehicle, "owner")
    if player ~= owner then
        AddPlayerChat(player, "You are not the owner of the vehicle!")
        return
    end
    SetVehiclePropertyValue(vehicle, "locked", not state, true)
    if state then
        AddPlayerChat(player, "You unlocked the vehicle!")
    else
        AddPlayerChat(player, "You locked the vehicle!")
    end
end)

local db = mariadb_connect("example.com", "tutorial", "b3rp4BQhc6J2RvLV", "tutorial")

AddEvent("OnPlayerSteamAuth", function(player)
    local name = GetPlayerName(player)
    local steamId = GetPlayerSteamId(player)
    mariadb_query(db, "SELECT * FROM users WHERE steam_id='"..steamId.."';", function()
        if mariadb_get_row_count() > 0 then
            AddPlayerChatAll(name.." (#"..mariadb_get_value_name_int(1, "id")..") joined the server!")
        else
            mariadb_query(db, "INSERT INTO users (steam_id, name) VALUES ('"..steamId.."', '"..mariadb_escape_string(db, name).."');", function()
                AddPlayerChatAll(name.." joined the server for the first time! He is player nr: "..mariadb_get_insert_id())
            end)
        end
    end)
end)