In order to apply to become a Thai permanent resident, applicants must have had a Thai non-immigrant visa for at least three years prior to the submission of the application and must have three consecutive yearly extensions in order to qualify. The maximum quota is 100 persons per nationality per year
I assume your goods are already in Thailand? It all depends on how long ago since you got your visa and the officer on duty on the day. My relocation company covered the duty as part of my package
Yes a B2 Visa is for the US. Are you retirement age/working/coming as a tourist?
As a tourist you can visit Thailand without a visa through the Visa Exemption Program. French citizens can stay in the country for up to 30 days as a tourist and can extend their permit to stay for a further 30 days at any local immigration office