The only piece of advice I give to highschoolers that want to get into research is to cold email undergrads with a good track record.
The only piece of advice I give to undergrads that want to get into research is to cold email PhD students with a good track record.
Most undergrads are bottlenecked by research ideas whereas good PhD students have way too many ideas that they cannot execute. If you can code reasonably well, PhD students will be more than happy to work with you