I hear [Biden] is instructed what to say and do, no?
Apparently not with regard to the policy regarding military withdrawal from Afghanistan.
In a decision that was Trumpian in its preference for instinct over expert advice, Biden, who throughout the Obama Administration reportedly wanted to end the U.S. military presence in Afghanistan, decided to proceed with Trump's withdrawal policy. He, like Trump, acted on strongly-held conviction as well as a political calculation that public opinion favored withdrawal. (Obama reportedly had felt the same at first, but as he learned more about the policy options and their implications, his decided not to act on his initial instinct.)
It probably will be quite some time before enough information becomes public knowledge to know for certain, but it seems likely the people in the government who were to become responsible for implementing the withdrawal were aware, and warned Biden and the appropriate political appointees of his Administration, that there was likely to be a loss of confidence within the Afghan national government and army once the United States began a noncombatant evacuation operation, even if they failed to anticipate that the Afghan army would collapse as quickly as it did. They also presumably figured there would be a hectic, difficult-to-manage scramble by civilians to leave the country once the U.S. military began its own withdrawal.
Biden, like Trump, made the policy decision. Other appointive and career officials were responsible for its implementation. I don't think anyone who wasn't privy to the latter process can know at this juncture whether there was a way to have carried out the implementation of the withdrawal that would have resulted in less chaos. It seems to me that once the policy was set by the previous Administration and reiterated (with minor modifications) by this one, the options available to the military and diplomatic officials charged with carrying it out were rather limited.