Withdraws, having sent up first course, including last of these (8)
I believe the answer is:
retreats
'withdraws' is the definition.
('retreat' can be a synonym of 'withdraw')
'sent up first course including last of these' is the wordplay.
'sent up' says the letters should be written backwards.
'first course' becomes 'starter' (first course in a meal).
'including' is an insertion indicator.
'last of' indicates one should take the final letters.
The final letter of 'these' is 'e'.
'starter' enclosing 'e' is 'staerter'.
'staerter' back-to-front is 'RETREATS'.
'having' is the link.
(Other definitions for retreats that I've seen before include "Goes back, like defeated army" , "Recedes" , "tactical withdrawals" , "Places that afford peace and quiet" , "Of army, falls back before enemy attack" .)