I'm planning to go to a tour that visits these countries:
I'm going from the UK via a ferry to Calais in France and then we take a bus to Amsterdam through Belgium.
Do I need to apply to Netherland to get my visa or to France as that's the first point of entry?
The rule is defined in article 5(1) of the Schengen Visa Code (regulation 810/2009):
The Member State competent for examining and deciding on an application for a uniform visa shall be:
(a) the Member State whose territory constitutes the sole destination of the visit(s);
(b) if the visit includes more than one destination, or if several separate visits are to be carried out within a period of two months, the Member State whose territory constitutes the main destination of the visit(s) in terms of the length of stay, counted in days, or the purpose of stay; or
(c) if no main destination can be determined, the Member State whose external border the applicant intends to cross in order to enter the territory of the Member States.
You're visiting several countries so (a) does not apply. You're staying the same number of days in several countries and none of them seem to be the main destination so (b) does not apply. You must therefore fall back on (c) and it's not ambiguous: the place where you enter “the territory of the Member States” (i.e. the Schengen area as a whole) is France.
There is no rule that you should rank countries by the duration of stay, apply to the first country you will visit among those that could be considered as the main destinations or anything like that. Unfortunately, this one seems to trip up many people including contributors to this site or, occasionally, consulates and outsourcing businesses like VFS.
The main thing you can do to mitigate potential issues is to apply as early as possible to give yourself time to resubmit the application to another consulate if need be. If the consulate you apply to declines to process the application, this would not count as a refusal, they should refund the application fee and return your documents.
