1. First of all, you should disable your antivirus. Click the Start Menu, type Windows Security and then click on it.

2. Click Manage settings.

3. Turn off every protection feature by clicking the respective button.

4. This is how it will look like after you disable the protection features.

5. Right-click on the ZIP file, then select Extract Here. If you’re asked for a password, enter 123 and then click OK.

6. Once the extraction process is finished, open the extracted folder.

7. Double-click on Set-up.exe.

8. If UAC pops up, click Yes. If not, you can directly perform the next step.

9. Click the Continue button.

10. Wait until the installation is completed.

11. Click the Close button.

12. You can now use Adobe Photoshop 2021 for free.