• 登山とざん — mountain climbing
• 登場とうじょう — appearance (on stage, etc.)
• 登録とうろく — registration
• 登校とうこう — attending school
• 登記とうき — registration (legal, official)
• 登用とうよう — appointment, promotion

登 shows the idea of ascending — step by step, like mounting stairs or a platform. It’s often used metaphorically in social settings, such as gaining a higher rank or registering officially. Its radical 癶 represents footsteps and upward movement.

山やまに登のぼって、美うつくしい景色けしきを見みました。
I climbed the mountain and saw a beautiful view.

サイトに 登録とうろくしてください。
Please register on the website.