This is from the help file.
Targeted Scan: scans folders that you specify. After clicking the Targeted Scan tile, tick the folder you want to scan and click OK. To modify this scan's parameters, click Settings beneath the Targeted Scan tile. Read more...
Explorer Scan: scans files or folders, similar to a Targeted Scan, but is conveniently available from the Windows context menu when you right-click a selected file or folder in your File Explorer or Desktop. Modify this scan's settings from the ☰ Menu ▸ Settings ▸ Protection ▸ Scans. Read more...