This depends heavily on your understanding of baptism and church doctrine. If you subscribe to the Apostle’s Creed or the more definitive Nicene Creed then a second baptism is a no no. If you believe baptism is a sacrament with permanent spiritual consequences then attempting to repeat it is sacrilegious. If you adhere, or wish to adhere to the practice of the early Church, second baptisms are not admissible unless the first was in some way defective or invalid (i.e. non-Trinitarian language or baptized by those clearly outside the Faith).
However if you believe baptism is merely an external ceremony of purely symbolic importance, then you can do it every day if you like.
My previous was intended as a reply to the OP #1.
In all examples of baptism in the NT, being baptized was the choice of the believer. Corrections welcome.