If many applicants possess the same skills, you can add the skills in bulk. To appoint the same skills to many applicants, you need to go to the Talent Pool and select the applicants you wish to appoint skills to. On the menu that will appear at the bottom of the screen, click on the three dots and then Add Skills.
To add skills, you can either type the skills you desire to add, or you can select the skills from the list which consist of the skills added from Settings. If you type a skill that is not on the list, then you should click on Create or press Enter.
After typing your desired skills, click on Assign Skills and you will see that the skills will be appointed to the applicant.