If you want to know whether the weather is good to fly then use the UAV Forecast app.
REMEMBER: You set the parameters, so if you think your drone will fly in a 25mph wind then set it up this way. (Good luck)
There are many sites around the UK where land is owned by the National Trust but unfortunately NT do not allow you to set off from their land (Although in quiet times I have found some friendly staff :-))
There aren't any rules about flying OVER National Trust land as long as you follow the Drone Code and any other local rules.
I find this link useful to find out where NT land is:
It is useful to know that you can't take off from National Trust land but you are allowed to take off from the Crown Estate (Land owned by the queen), as long as you follow the drone code. This map looks to tell you about both.
This is a "Must Have" application which can tell you lots of useful information about where you are planning to fly. Please check this before you fly.
Some drones like DJI drone keep masses of data about your flight which is interesting and useful.
AirData allows you to visualise your data for free using this website.
It tells you things like how your batteries are doing, is your drone turning quicker in one direction than another and suggests maintenance
I like to use Davinci Resolve. This is because it has loads of features and it is free!!!
It does take a bit of effort to learn but well worth the effort and lots of videos on YouTube to help you.
For help with Davinci Resolve ,there are plenty of YouTube videos but I found these 5 minute clips REALLY useful and easy to understand.