Thank you so much!
Unfortunately I do have another question, do any certain document copies need to be certified? Like copies of the passport, or marriage certificate? Etc
The documents you send as evidence should be original or a certified copy.
The photocopies of your original evidence can just be regular copies.
The marriage certificate you send should be original and send an additional photocopy for them to keep.
You send your original passport and previous passports with regular copies.
Your partner can provide a copy of their passport rather than the original, this should ideally be a certified copy. Then it's up to you if you send a copy of the certified copy or not.
Not sure if that is clear or not but when you finish, you're going to have one pile of original documents, and one pile of regular photocopies of those original documents.
Some of the original documents may be certified copies, eg your partners passport.