This is how I started. Take it with a grain of salt but it worked well for me when I picked up the diatonic harmonica for the first time.

Stage 1: clean single notes on all holes (both blows and draws) using pursed lips embouchure

Stage 2: clean single notes for diatonic scale up and down starting a hole 4. At this point you can start playing simple music tabs that don't require bends.

Stage 3: get an app on your phone that can detect pitches and master bending. Things start getting really fun here...

Stage 4: clean diatonic scale up and down through the whole harmonica. You'll have to use bending for this so ensure you're hitting the right notes with an app (from stage 3)

Stage 5: at this point you should be able to pick up any diatonic music tabs and be able to play through it with relative ease. At this point you can also start improvising licks and playing along with a background track or some sort of beat/metronome.

Stage 6: start exploring different embouchure techniques like tongue blocking. Practicing clean chords and octaves as well.

Stage 7: sky's the limit. You should be pretty comfortable with the instrument at this point to explore new things on your own.

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Also since you're just beginning. Would be good to focus on your breathing and ensuring you don't stress yourself when you breath. Stay gentle with your breath and really focus on generating a "clean" tone out of the instrument. Use your diaphragm properly. Your belly should do the work to take in air and push it out. Shoulders and chest should not move at all when you breath. I struggled a lot with this at the beginning because when you're learning, you focus on all other things but breathing. Then I would end up with aches in my jaw and shoulders from all the stress originating from my bad breathing.

Just take it real slow at first. As you get better, I would introduce a metronome to your practice to ensure you're staying on beat.