*Edited - I was using pointlessly long sentences.
Yup.
If your goal is gaining native/near-native fluency then there is no other option but to talk/write to people.
Lots of people will try to tell you "just use Anki", just use some AI-gimmick, just read books or just listen to lots of podcasts. But they are wrong.
The problem with the one-sided immersion as I listed above is that you will become very good at comprehension. You will be able to perfectly understand what people are saying, you will be able to perfectly understand complex written documents, or documents with lots of native slang and abbreviations.
But comprehension != fluency.
If you want to be able to speak and write like a native, then there's no shortcut. You have to get off your backside and interact with the natives in live bi-directional form.
AI will NOT help you with this. AI is very good at being very confident at being very wrong, that is not what you want. You want humans, real life humans, the more the better (then you get exposed to different dialects, different age groups etc. etc.).
If you absolutely must have an app, then look at something like HelloTalk which is basically 21st century pen-pals, find a human language partner and chat with them.
But really, just join a sports club, do some hobbies, go down the pub .. whatever gets you in the room with humans.
Also find a local group doing an activity you like. Walking in the woods, or knitting, or whatever. Join and use it as a chance to talk lots with the other people in the group.
The best way is to speak with people whenever you have a chance.
Move on to reading books - you can start with simple comic books like Tintin, Asterix, Archies etc. if you find reading "boring" at first. And later move on to kids / teens novels (I'd recommend British authors like Enid Blyton and JK Rowling). These will also give you an immersive experience to western culture.
Another enjoyable way to build up your vocabulary is to watch English TV series with English subtitles.
Finally, you do not need to be embarrassed about trying to talk with someone in broken english. You are trying to learn a new language and you should be proud of that. There are so many people in the world who can speak only one language, and they don't realise how much it limits the way they view the world. People are often unkind because of their narrow worldview. It has nothing to do with you because you are actually expanding your worldview, and it makes such people uncomfortable because they have never tried to do so. Just find somebody else to talk to - there are kind people everywhere.
Other than that - practice speaking as much as you can! Also, watch native speakers and focus on how they move their mouths to make sounds. Try to copy their speech cadence and repeat the phrases in their pronunciation and musicality. This is called shadowing and can be very effective (and free!)
Just out of curiosity, what is your native language?
One of the things that came to mind when considering your question… your struggles are likely common to other folks who share the same native language as you.
For example, certain sounds may be hard to make, and you're accustomed to saying certain letter combinations in one way for your native language that may be different for English.
If you can find others locally, who also share the same first language as you, they may be able to give you pointers to help with the same challenges.
I lived in China for a couple of years and worked really hard to learn Mandarin. The turning point for me was in the shape of my mouth. When speaking Mandarin, I had to close/tighten my mouth more than if I was speaking English. I think a lot of the tonal languages require you to close your mouth down, whereas English is spoken more with an open mouth. That can be tough and weird for people to do.
So my advice honestly is to try talking like a Texan. Talk with a big voice, amplify your voice, and open your mouth up.
I also recommend shadowing: listen and repeat English phrases frequently, literally say them out loud. This builds up the muscle memory needed to speak and think in another language quickly. You can do it with podcasts or tv shows too.
You're gonna do great!
That sounds like a way to acquire an unusual dialect that might even be more confusing to both native and non-native English speakers, especially those outside of the major cities who aren't already used to talking with non-native speakers.
If somebody wants to become fluent in Canadian English, they'll need to directly interact with native Canadian English speakers (or certain native American English speakers) for a prolonged period of time.
Even then, I know many non-native English speakers in Canada who can get by well enough day-to-day, but even after many decades of daily practice, daily use, and daily exposure in Canada, they're still quite far off from fluency in many ways.
What worked very well (from my point of view) for me, was binge watching American movies/shows. I would watch maybe 3 hours each day before going to bed, and I feel like my brain worked a lot on that while I was asleep.
As for what seems to be your introvert temperament, not sure what would work best. Maybe finding groups around you that do something you like.
Combined with things like using frequency lists in Anki and working exercises, and practicing speaking out loud, you can make a lot of progress.
So consider watching cartoons and other TV shows, movies, music, etc.
But nothing beats in-person. Find language meetups, social events, etc. The people who I know who get fluent fastest don't care about making mistakes and getting out there, most important thing is just to try and talk any chance you get!
Also reading books in English out loud can be really helpful.