One of the ways to absorb external pressure while still having structure is by making micro schedules and habits. You can use habits to get things done without scheduling and you can keep flexibility in your schedule by using small blocks of flexibility.
Deep work takes time. I like to block off at least 3 hours to get my own tasks done. It is always nice to have more, but 3 is about the minimum for me to get into a flow. Putting 3 hour work blocks back-to-back rarely works for me.
I try to structure, my schedule to optimize for as many separate work blocks as possible. I move meetings together and free up afternoons to make sure I can achieve my goals.
You’ll need to find what works for you, but one thing I know for sure is you need to be flexible because things change all the time.