You have full control over access roles for your TalentLyft account. Just as you added members you can also remove them.
After clicking on your Profile icon, go to App settings - Team members.
From the team members list, find the user that you want to delete and click on the Trash bin icon, next to his/her name.
Can I only change the access role without deleting the member?
Yes, the process is the same as above, just click on the Pen icon and choose the role you wish to give them.