Short answer is you can’t see historical data for updates unless you already had some auditing system in place at the time change happened.
What you can do is to try reading transaction log using some third party tool like ApexSQL Log and checking if there is info like this written somewhere in t. log.
I know there is a lot of historical data written in transaction log that can be used for auditing but I’m not 100% sure about finding username.
If you want to setup a system that will track this going forward you can try DDL triggers, SQL Traces and more…
The best way to do this would be to use extended events to capture logins so that you know precisely who is connecting to what. You can also add extended events to capture what queries they're running. But, you have to have it set up in order to capture this. Nothing built-in to the system automatically captures this type of information. However, you do have the option of looking at the cache to see what queries have been run, but not who ran them. You can look at sys.dm_exec_query_stats to see an aggregate of attributes about queries that are currently in cache. This won't do what you need, but it's an additional investigative tool you can use until you get the extended events set up.
Also, if luck favours you, you can try below steps:
- Loginto the instance.
- Go to security option
- Expand and right click on Logins
- click reports> Standard reports > Login statistics
Again a point to note, This report shows some information about logins, but it does not show historical information. Only the currently logged-in users are shown.