Weakness as an insecurity

I'm 17. Pretty unfit. I never thought strength would become my biggest insecurity?
I'm the weakest person that I know, genuinely and it's gotten to the point where I would like to go to the gym and work on it to make myself feel better and more confident and generally just healthy - however I literally can only lift like 10kg..
I feel that its just embarrassing, and I don't know where or how to start.
My friends invite me to go to the gym with them and help me but I'm too embarassed.
I just don't know what to do

start training at home, even if it's just push ups on an elevated surface. Do a crazy number go for a 100 a day and some tricep dips until you can start doing your own bodyweight, and then Id recommend to go to the gym alone, but remember that your friends are there to support you. Everybody starts somewhere. In a couple of months you'll feel a lot better about yourself

In reality the strong people tend to be better socially

Evidence to support that statement?

Evidence to support that statement?

Do callisthenics. The Recommended Routine in Reddit is good for that. However it doesn't train legs too frequently

I disagree. After 20-30 in a row you're basically just training endurance, you need to increase the intensity. So pushups, pushups leaned to one arm, archer pushups, 1-arm pushups

Tricep dips? I'd say bench dips and then bodyweight dips. Pullups for the lats, squats for the legs, calf raises for calllves etc.

In reality the strong people tend to be better socially

"Why are physically formidable men willingly allocated higher social status by others in cooperative groups? Ancestrally, physically formidable males would have been differentially equipped to generate benefits for groups by providing leadership services of within-group enforcement (e.g., implementing punishment of free riders) and between-group representation (e.g., negotiating with other coalitions). Therefore, we hypothesize that adaptations for social status allocation are designed to interpret men's physical formidability as a cue to these leadership abilities, and to allocate greater status to formidable men on this basis. These hypotheses were supported in 4 empirical studies wherein young adults rated standardized photos of subjects (targets) who were described as being part of a white-collar business consultancy. In Studies 1 and 2, male targets' physical strength positively predicted ratings of their projected status within the organization, and this effect was mediated by perceptions that stronger men possessed greater leadership abilities of within-group enforcement and between-group representation. Moreover, (a) these same patterns held whether status was conceptualized as overall ascendancy, prestige-based status, or dominance-based status, and (b) strong men who were perceived as aggressively self-interested were not allocated greater status. Finally, 2 experiments established the causality of physical formidability's effects on status-related perceptions by manipulating targets' relative strength (Study 3) and height (Study 4). In interpreting our findings, we argue that adaptations for formidability-based status allocation may have facilitated the evolution of group cooperation in humans and other primates."

Source: L. A. W. S. Z. L. A. C. R. JR; The role of Physical Formidability in human social status allocation. Journal of personality and social psychology (available at https://pubmed.ncbi.nlm.nih.gov/26653896/).

'Allocated' doesn't mean they are better.

Any advice to offer

As suggested, you can start to train at and from home. Use chairs and stairs. Walk. Walk with weights. Cycle. Find an online fitness programme to follw, even one for the Armed Forces. When you are more confident book fitness classes and an induction at a gym so a PT can advise on a programme.

And ignore the "bodybuilders have more social standing". If you are fit, healthy and good company, you'll very fine.