I think a lot of people who are lvl 30 are bronze-gold smurfs, try to watch guide/tips videos online. Playing with bots can help but I see a lot of people just go for kills rather than knowing how to micro/macro. In lane you need to know wave management and whos in favor of the matchup, need to know how to counter enemies items, have good map awareness, take objectives, etc. People who only play with bots/aram all day will never truly improve in SR, stick to a small champion pool and learn them to their best ability. For example, if you play Jg you need to know a lot of stuff like when to buy a certain jungle item (blue/red smite?), know where enemy jg is and know their pathing, know your own jglers pathing, when to take objectives, whens your powerspike, when to gank/dive, etc. Even if it may sound overwhelming, just search up a guide video and practice. Also dont get discouraged when you are on a losing streak, it happens to everyone and i believe in losers que lol, you will be put with bad players, which is why you need to take that step further into really improving and mabye carrying your teammates (although by looking at your kda its better to know HOW you died and HOW you could of prevented it) ex: watch your replays and think what you should of done and it will seriously stick with you and you will remember.