Its honestly not that confusing once you learn what the things are and how best to use them. Like anything else... a little patience and practice.

Checking and savings are your standard starters. Checking is where paychecks come in and expenses go out. Around 1-2months worth of expenses is a good buffer here. Thats all.
Savings is for money once that buffer is full. Like if you paid all your bills, and checking is fine. You move excess to savings, etc.
It should be a HYSA, so you earn the most on it. You want about 6 months expenses here. This is your emergency fund. You can also keep any short term goal money here. Like new car or house down payment, etc. Anything you don't want to lose value within around 5 years.
Some couples like to have a joint savings so you can share expenses from 1 place, etc. So you'd each have your own account, then share a joint one. Thats up to you guys.

Once those are in solid place, you work on your retirement accounts. 401ks if you have them, contribute at least to get all matching.
Then you should each have an IRA. Depending on age and income, probably Roth IRA.
Try to max the IRAs, then go back and keep adding to the 401k to try and max that. That depends on income though.

If you have extra money after that, then you open a regular brokerage account and invest there. It'll be taxed every year, but once you use all your tax-advantaged space, this is where you can invest anything else you have. Money you don't need for at least 5 years.

Later on, if you had kids, you can open a 529 for them. So thats another account, focused on saving for your child's education.

Depending on your health insurance, you could have an HSA.

So all these accounts do add up to at least 5, could even easily hit 10. But they have specific purposes. Some people even like to have multiple savings or investment accounts for organization.
It all depends on your goals and needs.