I honestly do not know enough about French or Spanish forests to know whether there are sufficient fire breaks in them.
One thing that governments could do, would be to ban the sale of disposable barbecues.
Obviously, just banning their use or the lighting of fires out-of-doors during heatwaves is never going to be enough, for there is no way forests, heaths etc. can be patrolled to check that people are actually obeying bans on open fires, camp-stoves, barbecues etc. during heat-waves.
Teaching school-children how to vehave responsibly on trekking or camping trips might do some good. After all, our generation were taught as girl guides or boy scouts how to safely light fires and put them out when on camping trips, to always break used matches in two and stick the ends of them down into the ground and either to bury rubbish or take it with us to the nearest bin.
Perhaps it is time for an enormous advertising campaign for fire prevention?