How can I overcome feeling dumb at my work?

I feel dumb at work because I think I cannot get simple things done. I’ve been working for over a year in my current role and I still find planning tasks so tricky at times. It’s just whenever I join this meeting, I always fail to foresee any issues or overestimate my goals. But there’s also this expectation from my supervisors to achieve more than I perceive can be done or sometimes they would see it as repetitive, and when I apply this thinking to another project, it will turn out different. I feel like I cannot meet their expectations and it is usually in these sprints that my goals and planned tasks are often called out as ‘ambituous’ or ‘too optimistic’. I never forget to ask beforehand but I feel like I sometimes can’t get what they want from me and I’m confused that this has led me to think that maybe I am just dumb.