Hello Shariar!
I see this error on my localhost, so it's impossible for you to connect to it, I'm using wamp server.
It is common for PHP 7.3 and 5.6 and you can see this Notice only at the administration side of Taxibooking on this page: Configuration Manager > Settings.
May be the copy of the error message will help you figure out what it is, my localhost configuration or real bug.
( ! ) Notice: Trying to get property 'params' of non-object in C:\wamp64\www\edsa-aramis_paris_com_test1\administrator\components\com_taxibooking\helpers\taxibooking.php on line 278
Call Stack
# Time Memory Function Location
1 0.0000 419992 {main}( ) ...\index.php:0
2 0.0570 1456000 Joomla\CMS\Application\AdministratorApplication->execute( ) ...\index.php:51
3 0.0570 1456000 Joomla\CMS\Application\AdministratorApplication->doExecute( ) ...\CMSApplication.php:196
4 0.3500 4501792 Joomla\CMS\Application\AdministratorApplication->dispatch( ) ...\AdministratorApplication.php:159
5 0.3510 4504504 Joomla\CMS\Component\ComponentHelper::renderComponent( ) ...\AdministratorApplication.php:101
6 0.3570 4695248 Joomla\CMS\Component\ComponentHelper::executeComponent( ) ...\ComponentHelper.php:377
7 0.3570 4712624 require_once( 'C:\wamp64\www\edsa-aramis_paris_com_test1\administrator\components\com_taxibooking\taxibooking.php' ) ...\ComponentHelper.php:402
8 0.3650 4820760 TaxiBookingController->execute( ) ...\taxibooking.php:62
9 0.3650 4820760 TaxiBookingController->display( ) ...\BaseController.php:710
10 0.3650 4820760 TaxiBookingController->display( ) ...\controller.php:61
11 0.3830 4911504 TaxibookingViewConfigs->display( ) ...\BaseController.php:672
12 0.3840 4911824 TaxibookingViewConfigs->get( ) ...\view.html.php:40
13 0.3840 4911864 TaxibookingModelConfigs->getItems( ) ...\HtmlView.php:425
14 0.3840 4912248 TaxibookingModelConfigs->_getListQuery( ) ...\ListModel.php:187
15 0.3840 4912712 TaxibookingModelConfigs->getListQuery( ) ...\ListModel.php:133
16 0.3840 4912712 TaxibookingHelper::checkReviewRequestSettings( )
Best regards.