Hello and welcome!
Yes, there are solutions/benefits of having a gmail account, if simply just to store contacts vs. storing them on the device itself.
If you happen to factory reset your device, your contacts are saved in gmail, and will reappear when signing back into your gmail account.
You can easily set up an account on your device by going to the settings/accounts and then select "add account"
Or you can find your gmail icon, and set it up from there.
Now, back to your issue of losing contacts, do they just.... disappear??? Are you saving them on the phone or sim card?
Do you have a data connection either with 4g, or wifi?