Laravel: Pass Variables in View to Controller

I want to pass two variables from the form in the view to my controller and there to use them... But I don't know how...

Can you help me?

shop.blade.php:

<div class="mcitem">
                    <img src="/images/shop/Stein.png" alt="Stein">
                    <div class="mcunits">
                        
                        
                    </div>
                    <div class="mcbuy">
                        $itemid = 1;
                        $bprice = 3;
                        
                    </div>
                    <div class="mcsell">
                        
                        
                    </div>
                </div>

ShopController:

public function add(Request $request){
    $this->validate($request, [
        'units' => 'required|min:1',
    ]);
    if(Input::Get('buybtn')) {
        $this->Buy(); //if Buy Button is pushed
    } elseif(Input::Get('sellbtn')) {
        $this->Sell(); //if Sell Button is pushed
    }
}

public function Buy(){
    $username = Auth::user()->name;
    $units = Input::Get('units');
    if((DB::table('users')->where('name', $username)->value('kontostand')) >= ($bprice*$units)){
        $check_entry = DB::table($username)->where('Item', '=', $itemid)->first();
        if(is_null($check_entry)){
            $hunits = DB::table($username)->where('Item', $itemid)->select('units')->get();
            DB::table($username)->where('Item', $itemid)->update([$itemid => $hunits + $units]);
        }
        else{
            DB::table($username)->where('Item', $itemid)->insert(
                [$itemid => $units]
            );
        }
    }
    else{
        echo "Zu wenig Geld auf dem Kontostand!";
    }
}

I know now it's completly wrong because I tried so much but yeah...Nothing happens...

via Chebli Mohamed