There are a lot of settings to navigate though in your NVR, and its often recommended to leave things at their default if you don't know what they do. However there are a few settings you should definitely change and apply to improve the overall performance of your system.

If your system seems to have a slower remote connection when you are away from your home network, or you cannot connect to it at all, the DNS may not be set to an appropriate address. In the NVRs settings the DNS is automatically assigned an address via your routers DHCP, and sometimes it will set the DNS field in the NVR to an address like 192.168.1.1 or 192.168.0.1. This is often the routers IP address, and while it can technically act as a DNS server it tends to do a pretty bad job at it. Regardless of what address is currently in there, we recommend using Cloudflares DNS address since it is both fast and secure

To set it manually, go to Main Menu > Network > TCP/IP

Disable DHCP for DNS so you can manually enter the following:
Preferred DNS - 1.1.1.1
Alternate DNS - 1.0.0.1

You can alternatively use Googles DNS Address:
Preferred DNS - 8.8.8.8
Alternate DNS - 8.8.4.4

Don't forget to click Apply!

If your system time is off it can make it difficult finding certain events in playback and sometimes cause seemingly unrelated issues. As long as your NVR is connected to the internet via your router, you can sync your NVRs system time to a Network Time Protocol or NTP server.
To set this, go to Main Menu >System > Date&Time.
First and foremost make sure you have your time zone set to your correct time zone, from there you can copy the rest as its displayed in this example.

Enable DST, set Type to Week, then enter the following for Start and End time:
Start Time: Mar 2nd Sun 02:00

End Time: Nov 1st Sun 02:00

Then enable NTP and setting the Server Address to us.pool.ntp.org click on Manual Update. Also make sure Port is 123.

Don't forget to click Save near the Time Zone at the top and Apply when done.

If you are running low on storage on your NVR there are a couple things you can do to optimize your cameras. Go to Main Menu > Camera > Encode
From here, make sure you have Sub Stream Video Enabled.
Set Coding Strategy to General, if AI Coding is an option select it.

Compression should be set to H.265 for both Main and Sub Stream.
For Resolution and Frame rate set them to the highest option for the best clarity.
Bit Rate Type should be CBR
Bit rate for 4K resolution should be 4096Kbps, 2K = 2048Kbps
Sub Stream bit rate can be 512Kbps or 1024Kbps

If your cameras have a built in microphone you will see More buttons below the bit rates. Microphones are usually disabled by default to comply with state laws but if its legal where you live you can enable this!

Compression is usually G.711a be default but you can set this to AAC which lets you choose a higher Sampling Frequency, resulting in clearer Audio!
Make sure to click OK and Apply to save your changes!