I just receive errors when trying to build mobile

I am new in the development in Android and i am having some problems in my learning. I am trying to build my solution in my cellphone, he is a Android of version 6.0. I fetched for some tutorials in the internet and even here in the Stack Overflow and because of it a downloaded all the versions of android sdk, since the 5.0 until the 7.1.1 and even the extra packages. Even so i continue receiving the same errors when i try to build my solution. They follow below:

FAILURE: Build failed with an exception. Where: LuppApp Build file 'C:\Oxaguia spk\Trabalhos\Coach IT\Visual Studio\LuppICS\SolutionLupp\LuppApp\platforms\android\build.gradle' line: 289
What went wrong: LuppApp 1
A problem occurred evaluating root project 'android'. LuppApp 1
Keystore file does not exist: c:\lupp-Release.keystore LuppApp 1
Try: LuppApp 1
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. LuppApp 1
Error: cmd: Command failed with exit code 1 Error output: LuppApp 1
FAILURE: Build failed with an exception. LuppApp 1
Where: LuppApp 1
Build file 'C:\Oxaguia spk\Trabalhos\Coach IT\Visual Studio\LuppICS\SolutionLupp\LuppApp\platforms\android\build.gradle' line: 289 LuppApp 1
What went wrong: LuppApp 1
A problem occurred evaluating root project 'android'. LuppApp 1
Keystore file does not exist: c:\lupp-Release.keystore LuppApp 1
Try: LuppApp 1
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. LuppApp 1
Picked up _JAVA_OPTIONS: -Xmx512M LuppApp 1

I will be really grateful for everyone who can help me. Thank you.

SQL - PHP Multiple Set

im busy trying to set multiple fields in my DB and it is not working for some reason. Can you take a look and let me know where i have gone wrong? Thank you

<?php
error_reporting('E_ALL');
include 'db_header.php';

$id = $_GET['ID'];
$bronzeTokens = $_GET['bronzeTokens'];
$silverTokens = $_GET['silverTokens'];
$goldTokens = $_GET['goldTokens'];
$platinumTokens = $_GET['platinumTokens'];

$sql = "UPDATE Player SET bronzeTokens = $bronzeTokens, goldTokens = $goldTokens, silverTokens = $silverTokens, platinumTokens = $platinumTokens WHERE ID = $id";
$result = $conn->query($sql);
?>

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I have probably stupied question and simple, but i can't really find anything about that on internet.

Let's say I have an application for bookkeeping records, and I want to I host the application to enable the user to register and to pay usage on a monthly basis, but that every new registered user, you probably need to get a new instance of whether the database in order to data were each protected by another user?

Now, I do not understand how these apps, they call it? Web service applications or how? and say that terminology is necessary to search the Internet to know where to go and take a look at how to do something like that?

I sincerely apologize for this kind of question, but I really need some help because I do not know where to start.

Thank you for your understanding

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i have an app to manage students mark and i want to make a login for students

Image's link

when students try to login : the app should check if username/password exists in database

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What I want to achieve is either this:

Or this:

Current Code:

<md-input-container  ng-if="!ctl.module.activeDate" placeholder = "NotSetted">
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    <md-datepicker ng-model="" disabled></md-datepicker>
</md-input-container>

This implementation is using angular material. I check with the ng-if if the activeDate is null, if it's not I have another md-input-container that get's the value, that is a "workaround" solution, the best way would be to have all of that logic in the same md-input-container.

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• It doesn't have a scrollbar. I have to drag and drop using the mouse. It is really untuitive in a web browser.
• I can't copy the text to paste it elsewhere.

Maybe I just need to make some CSS adjustments.

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