There are several options to use and try CHR free of charge.
The free license level allows CHR to run indefinitely. It is limited to 1Mbps upload per interface. All the rest of the features provided by CHR are available without restrictions. To use this, all you have to do is download disk image file from our download page and create a virtual guest.
This requires that your router have an internet connection, DNS and that you have a MikroTik account.
After connecting, the free CHR will change to a 60-day trial of the license type you have chosen - P1 (1 gigabit) is the default.
To upgrade your trial to a paid license, go to https://mikrotik.com/client/cloudhosting (Account ⇢ All CHR keys) and click Upgrade next to the System ID that matches the one from the router license screen. Next, you may choose a license level and then pay for the license using credit card (CC), Paypal, a previously deposited amount, or you can use a prepaid license.
After licensing a running trial system, you must manually run the /system license renew function on the CHR to activate the license.
If you do not renew the license on the router before the 60 day trial end, your license menu will show "Limited upgrades", and you can no longer upgrade the RouterOS software on the CHR. The CHR id will also be removed from you www.mikrotik.com account, so to license it you will have to do a complete fresh CHR installation, request a new trial and then license it with the license obtained.
For more information on licensing, read wiki.mikrotik.com/wiki/Manual:CHR#Paid_licenses.