As you're going to be using your audio interface I'd not worry about an amp for now. Decent headphones or the in-ears you already own are fine.
Instead you could get a preamp like the behringer v-tone bass bddi21 to give your bass tone some flavour.
Budget for a comfortable strap and the correct cables, maybe a gig bag if you plan on taking the bass to different places (Thomann offers a package deal, not bad!)
Put the rest of your budget towards lessons, a quality audio interface if needed, or a DAW and plugins or a spare set of strings.
Most of all, enjoy and keep at it!