.htaccess \ index.php setting my blog folder as homepage

Hi guys.
Have recently had to transfer hosts as my previous one were just far too slow.

Anyway, got everything migrated easily, which i didnt expect to happen, but now i have one problem that I just dont understand.

Firstly:
I cannot seem to set the index.php in the eurythmics.me.uk/blog folder as my homepage, despite following these instructions.

https://codex.www.ads-software.com/Giving_WordPress_Its_Own_Directory

I have had to create a temporary index.html file that loads the index.php that now resides in my root.

When i follow the insturction above, i get an error 404 and the main page is not displayed, yet my searchable content and more is.

Secondly, im using Arthemia Premium as a theme, but the search bar appears to have stopped functioning at the top of the page.

Finally – And this is causing me a lot of grief, for some reason, i can no longer see any of my atom or RSS feeds, my posts are no longer getting google ranked which they were previously, and quite highly too.

Any help anyone can give on these 3 would be incredibly well received. If it works, i’ll make a donation to the Annie Lennox Sing campaign. See https://www.annielennoxsings.com for more info.

Thanks all.

Steve