@stfu-kun I've never been in a relationship, nor have I gotten interests into one, but having a friend who was in the very same situations as you multiple times, all I can tell you is the following:
1st have a chat with the girl in your English class
2nd try and ask your gf out, if she refuses and says she has plans, don't make it a big deal unless it's something that always happened whenever you asked her out
3rd Make a decision rather you think your English crush is a better person to be with or if it is ur current gf (which obviously isn't)
4th if you believe you'd rather be with the girl in ur English class take things slowly but not to slowly, don't go too fast, ask her out, take her places she'd like to go I know this sounds super clichés and all but it is sometimes the best options rather than rushing things
5th whenever you feel like it's time, confess to her
Again I am not in any relationship nor am I interested into getting in one, my advices are probably the worst but I still hope it helped
(ksjisbsidbissisbsibsisbs this was ages agoo but yeaaaaaaaaaah I'm still answering that)