Windows How do you check multiple emails on one app/software on pc

Here's an update.
So I tried Betterbird again and Thunderbird too, but still couldn't get accustomed to the age old UI.
Tried Outlook (new), even though there are a few features missing, especially "unread first", the UI is still pleasing for me based on the other apps I tried. Notifications are working fine and there is a few seconds of delay, doesn't come immediately though. I have to check if something can be done about this. But overall, because of UI alone, I am presently going ahead with Outlook only.

There seems to be other ones too which are subscription/fee based, but I'm only looking for free or economical ones.
Will let you know if I try anything else again. Even though not 100% satisfied with outlook, this seems only the better one overall.
Let me know what you guys think.
 
Are you trying this on a Windows PC / laptop or tablet kind of device ?
You can apply themes aka skin on Thunderbird which can suit your expectations.