The best value for wireless deployments:
MikroTik checks license validity at update time. Cracked licenses fail checks and won't update. Manual installs from untrusted repos are how systems get backdoored. Crack BEST Mikrotik License Key
MikroTik is excellent, but there are capable free alternatives if your budget is truly zero. The best value for wireless deployments: MikroTik checks
Once you have a proper license, here's how to get the most from it: or low-bandwidth backup links.
After 24 hours without a paid license, the system reverts to Level 1.
As mentioned, the CHR free license gives you 1Mbps throughput forever - enough for basic testing, learning, or low-bandwidth backup links.