Those active online get cheapish accommodation (6)
I believe the answer is:
hostel
'cheapish accommodation' is the definition.
(type of low-cost accommodation)
'those active online' is the wordplay.
'active' indicates an anagram (the letters are active/moving).
'online' becomes 'l' (I am not sure about this - if you are sure you should believe this answer much more).
'those' with letters rearranged gives 'hoste'.
'hoste'+'l'='HOSTEL'
'get' is the link.
(Other definitions for hostel that I've seen before include "Cheap accommodation for students, etc" , "Temporary home for the hiker" , "Inn" , "Inexpensive lodging house" , "Inexpensive accommodation as for back-packers" .)