There are a handful of starter weapons in Warframe. More than you might think, actually. When you play the opening tutorial, escaping from the clutches of Captain Vor and getting to your ship, you get a basic choice of weaponry, but there are also options in the Market once you’ve completed the tutorial.
The first weapons you pick up are a single Primary weapon, Secondary weapon and melee weapon. These are your starter weapons, and you’ll be using them for a while, at the very least until they are level 30.
Luckily, melee weapons it doesn’t really matter too much what you pick, it’s more what you prefer. The MK1-Bo is a slow but long-ranged staff with a nice thwacking sound as you hit people. It has a slow attack speed, but if you pick Volt as your starter Warframe, that’s not an issue as his Speed ability increases attack speed. The Skana is a basic sword, and is your best choice if you pick Excalibur as your starter Warframe, as you get extra 10% attack speed and damage with all sword weapons as your passive. If you picked Mag, feel free to pick which one looks nicest, but the MK1-Bo might be ideal due to its longer range. While the MK1-Bo does slightly more damage, some of this is offset by the slower attack speed, and is mostly countered by Excalibur’s sword-damage-increasing passive.
For secondaries, I’ll be honest, both the MK1-Kunai and the Lato are not great weapons. The MK1-Kunai are weak, silent, projectile-based throwing kunai thingies, which are ideal as a stealthy side weapon. The MK1-Kunai is a better choice if you picked the MK1-Braton, so you have a stealthy option if needed, and it also comes with two V polarities, meaning mods like Hornet Strike, the base damage mod for secondaries, costs far less slots. The Lato on the other hand is an incredibly boring hitscan pistol that looks and feels mediocre. The Lato has no polarities, but can be used to make the slightly stronger Bolto secondary weapon.
I’d recommend taking the MK1-Kunai since it does more damage than the Lato and has more modding options.
When it comes to primaries, it’s a funny choice. You have to choose between some sort of automatic rifle, the MK1-Braton, and a bow, the MK1-Paris. Both weapons have two superior versions, the normal Braton and Paris, and the Braton Prime and Paris Prime. The MK1-Braton is an automatic hitscan weapon, a good, well-balanced weapon, but also rather loud, while the MK1-Paris is a silent but deadly bow.
Both weapons are perfectly good, but as you face more and more enemies, you’ll begin to struggle with the MK1-Paris. It does excel in Spy missions and Exterminate missions where you can take enemies out one at a time (and perhaps get a nice stealth bonus too). The MK1-Braton at least has enough rounds to take a breather. Early on, ammo may be an issue, but rifle ammo seems to be more common than sniper ammo, which is what the MK1-Paris uses.
It is worth keeping in mind, no matter what weapon you pick, all MK1 weapons are available in the marketplace for a set credit value (generally 15,000 credits).
There are also a handful of other weapons available in the market. The MK1-Strun is a weaker version of the Strun shotgun, available for 15,000 credits and the MK1-Furax is a fist-based punching weapon, also available for 15,000 credits. Avoid the MK1-Furis, as it is a weaker version of the Furis, the blueprint of which is available as a reward for completing the Venus junction.
Finally, the Lex, costing 50,000 credits, is a powerful pistol, a worthy replacement of both the MK1-Kunai and the Lato. It’s a good investment once you’ve leveled up your starting pistol.
Most other weapons require various ingredients. You can buy their blueprints in the Market in your ship, or in Dojos if you are a member of a clan. New weapons can be built in the Foundry in your ship. The earliest weapon you can build is the Furis, which is essentially an upgrade to the Lato, and definitely worth using in early levels, but you can also obtain the blueprints for the normal (and stronger) Braton, Paris, Kunai, Bo, Strun and Furax in the Market.
At the end of the day, take what you feel you’ll prefer, and don’t worry too much if you aren’t a fan of your chosen weapons. You’ll get better weapons in no time at all!
Good luck out there, Tenno!