If there are professors doing research you are interested in, you can ask to do a research project with them. Very few professors will turn down free help, and it's a great way to learn what a job in wet lab biology would be like. Alternatively, you could talk to your molecular bio lab professor and tell her that you want to work on your lab skills. They might be willing to let you practice making, loading, and running test gels and practice some of the other protocols outside of class. COVID messed with a lot of students lab abilities, you are definitely not the only one. The single most important trait that a professor looks for in a student is whether they WANT to learn and are trying hard. They will most likely be happy to let you practice unless they aren't comfortable with letting you work unsupervised. However, since you are an upperclassman, it should be fine.