It is all explained on the Gatwick airport website at https://www.gatwickairport.com/at-the-airport/flying-in/flight-connections/
Because the paragraph is quite short I have also copied it below:-
If you are connecting on to another flight through Gatwick there are
different rules you need to follow depending where you’re arriving
from and departing to, whether your hold bags are checked through to
your final destination and if you have your boarding card.
Minimum connection times If you are connecting onto another flight at
Gatwick and you already hold a boarding pass for your onward flight,
we recommend that you allow a minimum connection time of 60 minutes
for same terminal transfers and 90 minutes if your flights arrive and
depart from different terminals. Your airline may have different
minimum connection time requirements, so please always check with them
before you book your onward connection.
If you have to collect your bags and clear immigration before
checking-in for another flight we suggest you check with that airline
for their minimum connection time.
...
International to international flight connections If you’re arriving
at Gatwick from an international flight, are connecting on to another
international destination you have some choices to make depending on
your circumstances:
(1). If your hold bags are through checked or you’re travelling with hand luggage only and you have your boarding pass, simply follow signs
for Flight Connections*. There is no need to clear Passport Control or
Customs.
or
(2). If your hold bags are not through checked, you must collect them at Gatwick. Follow signs to Baggage Reclaim – you will need to pass
through Passport Control on your way – and then either use our free
GatwickConnects service or proceed to the check-in desk for your next
flight.
Please note that all easyJet passengers must follow option 2 above,
even if you are travelling with hand luggage only.
