Hi Kirsty, welcome to the site.
Transgender is an umbrella term, for someone who doesn’t feel they align with the gender assigned at birth. This could mean the opposite binary (male to female or female to male) and something in-between (non-binary, transmasculine, transfeminine, agender, gender-fluid). Some transgender people may need to change their title (Mr/Ms/Mx), name, pronouns (He/She/They), dress/presentation, hormones or undergo one or more surgeries, some may need to some of these, and some can cope without needing any of these. Everyone has different triggers, and different levels of gender dysphoria. Not needing or not having access to medical care, including hormones or surgery, does not make anyone less transgender. I hope this helps.