Make A flexible time feature

Hello,

can there be fleixble times for tasks that we don’t relaly know how long we take ? And when we get it done there should be an automatic feautre that moves other tasks we have down. Lets say we get up at 8 am and then start working after 30 minutes we don’t know how long a certain task will take but we input all of them, the first one is the one thats probably gonna take longest we can press end clock or something to stop the timer when we’re done or need to move onto something that is nonegotiable. We should also have a nonegotiables feature where for example if we have a meeting we must attend that cannot be moved we have to schedule aroudn that time block instead.