Wait some time, not all the good modules e-adn plguins are updated to J4! yet.
I urge you to stay on J!3 for update,
but if you will create a new site, start with J!4
thanks for the share, but if you use yoothemepro, most of the widgets alredy imported inside the builder,
but if you have some other theme, this widgets are the best
this rsforms is definitely the best form plugin in joomla, you can save db, export to pdf whatever you desing, you can make calculations in it. thanks for the share