There's Room for You
Don't compare yourself to others... their progress and success with yours. There will always be some ahead of you and some behind you, and others with whom you keep stride. To become the best version of yourself requires you to be inspired to aspire.
Use their examples to elevate and motivate you. Be glad for their success and learn from it and you will have more of your own.
On the journey of pursuing your dreams and creating more meaning in your life, there are always moments of doubt. That's normal.