Concerns about moving my WordPress folder

Hello all, when i first started my site, I intended on using a splash page before people entered my site. I have now realized that is not what I want to happen, that i would rather it be in my domain.com rather then domain.com/subfolder

i realize it was bad planning, but there is nothing I can do about that now. i am concerned that my sites google search results are hurt by the fact my site right now redirects from domain.com to domain.com/subfolder

I have found the doc on how to move your site from a subfolder to the root directory, but i am very uneasy about doing this. my main concern is the amount of posts i have becoming dead links. will have to edit all of the links of my posts/pages individually, or will wordpress do that automatically?

I just want to be sure that my site isn’t being ignored by google because domain.com redirects domain.com/subfolder

can anyone tell me their experience with moving wordpress from subfolders to the root folder? any info would be appreciated.