OK now it should be easier. I got a good SQL Backup from my Provider. My problem was i missed the last PHP Update and my provider allows nothing under php 7.4 anymore.
Is it possible, that I just new install my shop in the latest version and just import the SQL and file-Backup?
EDIT:
I made a new Installation on the Server following these advices on "Update Prestashop" and I imported the old Database via Provider Import. The Shop is there now in similar condition like my old shop, but i can't login in my backend, also i can not login/register in the front end. 500 Server Error.
I looked in the Server protocolls and it seems that some hooks are not correct:
AH01071: Got error 'PHP message: PHP Deprecated: The hook "Header" is deprecated, please use "displayHeader" instead in module "ps_imageslider". in /httpdocs/classes/Hook.php on line 914; PHP message: PHP Deprecated: The hook "Header" is deprecated, please use "displayHeader" instead in module "klarnapaymentsofficial". in /httpdocs/classes/Hook.php on line 914; PHP message: PHP Deprecated: The hook "Header" is deprecated, please use "displayHeader" instead in module "dhldp". in /httpdocs/classes/Hook.php on line 914; PHP message: PHP Deprecated: The hook "Header" is deprecated, please use "displayHeader" instead in module "jmango360pwa". in /httpdocs/classes/Hook.php on line 914; PHP message: PHP Deprecated: The hook "Header" is deprecated, please use "displayHeader" instead in module "ps_legalcompliance". in /httpdocs/classes/Hook.php on line 914; PHP message: PHP Deprecated: The hook "Header" is deprecated, please use "displayHeader" instead in module "emarketing". in /httpdocs/classes/Hook.php on line 914; PHP message: PHP Deprecated: The hook "Header" is deprecated, please use "displayHeader" instead in module "ps_feeder". in /httpdocs/classes/Hook.php on line 914; PHP message: PHP Deprecated: The hook "Header" is deprecated, please use "displayHeader" instead in module "dhlefn". in /httpdocs/classes/Hook.php on line 914'
I assume I am close to my goal, but here it gets tricky to me. and I am still a newbie in this regards. How can I fix it?