I am a newbie starting with Confluence. I read few articles to find solution for 1st task I have to finish. I read some articles, but I don't know the best solution. Some suggest CSS, some Look and Feel.
1. Put a header and footer to all pages (Global header & footer)
2. Inset few buttons with text in header (e.g. Text with hyperlink to another page (e.g. Policy) ) . Same with footer (e.g. Terms and Conditions), it should navigate to T&C page.
3. Append text (si) to Company logo(image) ABC to make it look like ABCsi. On hover over Company logo , it should expand "si" to Staff Intranet.
Please suggest a good approach.
I think you read the documentation for confluence server.
But you are on confluence cloud. Here, there is no custom CSS possible.
On Atlassian Cloud, Confluence uses a custom theme that can't be modified or updated using custom HTML or CSS. For more information on custom themes in Confluence Cloud, refer to Working with Themes.
For the header and the footer, you can go to the settings and choose Header and Footer. There you can set the header or footer.
Were you able to insert CSS in the footer to make style changes?
Having an override style feature for Confluence cloud would be a great feature rather than force people to buy something from the marketplace to implement some basic changes. The product out of the box is very limited. You can get much better features from a free opensource product.
I would not try to do this on plain Confluence (Cloud or Server), it's a lot of work, most of it can't be done on Cloud (server may need some quite heavy coding), and will almost certainly end up as a mess.
Instead, I would look to using a theme app to re-skin your Confluence UI.