Hi to every one

(I have looked through the forum but need more basic help.. I am having difficulty with Header manager. I have installed the plugin but am a complete novice as regards to Piwigo. I run a word press business website url below. Recently i moved from Media upload wordpress default to Piwigo. What i need to achieve is a logo next to my title. On the forum it do's explain a lot about this topic. But not where to place the code. kind regards Ian )

Piwigo version: 2.10.2
PHP version: php73
MySQL version:
Piwigo URL: https://www.splinterlandscapes.com/portfolio/