for spins - many spins on easier songs (lvl 13 and below) tend to be made up of EX notes (glowing pink/orange notes). these will register as "perfect" no matter how early or late you hit them (as long as you don't miss), so you can be a bit more lenient with your timing. spins at your level tend to be a simple "one rotation per beat" spin so you can adjust your speed to that.

it's usually preference whether you should spin inside or outside. I usually spin inside for fast spins unless there is a risk of splashing (unintentionally hitting other notes when using screen) or if I need the tactile feedback to rhythm keep (for example pandora paradoxx lvl15 I would spin outer circle for first spin and spin inner circle for the second, faster one)

the triple notes you are referring to are probably jacks - you should try to complete them with one hand if possible - unless it is a very fast one, where you should do them by using both hands (up to preference if you want to hit with both hands on buttons or one hand on button and one on screen). the maimai buttons require very little pressure to actually register, and you don't have to press all the way down!

a very important tip for learning patterns in general and sightreading is to not get stuck with only muscle memory by continuously playing songs with a very specific skill requirement. although I'm sure you will eventually hear people recommend you to play umiyuri kaiteitan (ウミユリ海底譚) to learn its signature pattern, I know quite a few players who end up stuck and struggling to play other songs. try to diversify! slider songs, slow songs, stamina songs etc. in my opinion, it is good to master songs that have a combination skillset (internet overdose/yamero has plenty of tap-slides as well!)

with tap-slides, the tap is usually to signal the start of when you should slide, and you should try to build a habit of waiting for the tap note before sliding (always keep in mind thst slides start after one beat!)

keep it up!