If you want to set the Logo image in center of the header, go to Header builder > change positions of elements in the header content area. An example you can find in the Private Content area.
Logo size depends on your needs, for example, 2 columns – https://prnt.sc/iFcJ-aoKbtGJ width – 170px
One standard license is valid only for 1 project. Running multiple projects on a single license is a copyright violation.