For Dadof3:
I agree with all that JCG and BOF have said about choosing colleges. I'm guessing you were asking about baseball, too 
If he is a 2023 RHP already touching 90, LHP touching 86, or he runs a sub-7.0 60, or has exit velo 90+, or some other outstanding characteristic, then this is the recruiting summer for D1. And of course he needs to be able to play, to hit good pitching, to get good hitters out, to have the 6th tool, etc. In that case, yes, you can send emails with video, and tell schools where his team will be playing this summer. But, it's more useful if his coach makes the contacts for him. Summer coaches who prioritize recruiting will contact colleges that are a baseball (and academic) fit. Summer coaches usually want their players to commit to the highest feasible level; at the same time, they won't risk their reputations to recommend players to schools they don't fit.
Is your son on a summer team that has experience with college recruiting?
1. If yes, ask that coach what schools are feasible for him, baseball-wise. If the coach says he is D1 recruitable this summer, you should have a conversation, come up with a list of schools to give that coach (as above), ask the coach what the plan for him for this summer is. Communicate with that coach, ask him if you should send emails.
2. If no, get him evaluated, at PBR, or another showcase, or by someone local. If that entity/person says he is D1 recruitable this summer, figure out a plan for this summer (via email, perhaps) to get him in front of schools that are feasible, whether that's camps, showcases, tournaments with his team, etc.
Note the coach/evaluator needs to say "D1 recruitable this summer," not "could be D1 if he does xxx." If he is not (yet) a D1 player, play this summer to get better, re-evaluate at the end of the summer; '22 will be his recruiting summer.
I say this as a D3 parent who was completely confused at the stage you are now, stumbled through things, figured out a lot of stuff in hindsight.