Hello alexwasnotfound,
If you are beginner I might have some tips for which kit to buy: (Note : This is my personal reference since I have used tons of kits before, All mentioned here are for beginners since they don't have tons of coins to buy the expensive ones, the rest of it depends on you which kit you wanna buy)
#1 > Spy kit (20k) : In this kit you have to sneak 1 or sometimes 2 times to activate invisibility, It is a really great kit for destroying nexus since It gives you invisibility and people will not be able to see you, however they can see your foot particles. It only cost 20k coins which is great for this kit, there are tons of more things you can do with this but I mentioned only the main.
#2 > Sprinter Kit (35k) : This kit gives you the ability to have speed effect (infinite) and a splash speed pot, a bow, a stick with sharpness 1 and knockback 1 on it, It only costs 35k. It is really good if you are doing rushing, farming kills etc. This kit is also good If you have a good gear and don't wanna spend you time on tons of pots of speed and like the spy kit I only mentioned several things about this kit.
#3 > Tank kit (35k) : This a really great kit for rushing + defending, It gives you extra 2 hearts (4 if upgraded) and chain armor with chestplate (Prot 2) Leggings (Prot 1) and a wooden sword a wood pick + axe, It really helps you with rushing and defending since you can upgrade your gear and have 2 extra hearts but it also comes with slowness (infinite) effect which is not really that great however for urgent def It is good, It only costs 35k coins and you can farm tons of kills with this kit and destroy nexus since with this kit having extra hearts, It gives you advantage against other players, they cannot kill you easily, as all kits mentioned above I didn't mentioned all of it uses too.
Note : 35k is not really that expensive since you can get them by just winning games (TB gives you more coins than bw and sw) completing missions and contracts, there are some more inexpensive kits than these but I will recommend these kits since they are more useful (personal reference) rest is up to you, either which kit you want to buy, but these are my personal reference, hope this helps, have fun playing TheBridge Player!